Peter’s Epistles #29

Maintaining a Sound Christian Offense in our Spiritual Warfare 

1st Peter 1:13

(also available on-line at ichthys.com)
by Dr. Robert D. Luginbill

1st Peter 1:13

Therefore, gird up the loins of your mind in spiritually mature alertness, and set your hope upon that grace which is coming your way when Jesus Christ is revealed.
1st Peter 1:13

Therefore:  Peter's use of dio (dio/) in lieu of other more common Greek conjunctions here has the effect of connecting verse thirteen very closely with what has just come before:  the reason why we need to "gird up" our minds in level-headed gravity, focusing our thinking upon "the things to come", is because that posture of right-thinking and forward-thinking is the proper result of recognizing the blessings we possess as believers in Jesus Christ.  And we are believers in Jesus Christ.  That is truly who we are.  But the world is a "noisy" place, and it is filled with distractions, many of them being merely part and parcel of living in this world, many of them specifically designed by the evil one as part of his system to lead believers astray or at the very least to neutralize us and subvert our forward progress.  We have a Lord in heaven who died for us, Jesus Christ whom we claim to love with all our hearts.  Meanwhile, the angels are watching us to see how these truths affect us – do we really live as if we appreciated this so-great salvation, as if we really did love Jesus more than this world?  Learning what the Bible has to say about eternity, becoming proficient at applying that and other truths to the suffering and trials of this life, and maintaining an alertness about doing so is a major part of successful spiritual warfare whereby we may enthusiastically answer "Yes!" to the question just posed.

Gird up the loins of your mind in spiritually mature alertness:  The first thing to notice about this Holy Spirit-inspired command from the apostle Peter is that it involves taking positive action from the inside out.  Having reminded us of all the wonders of salvation we as born-again Christians possess (and will enjoy in the future), Peter now moves on to tell us how we ought to behave in this life as a result.  But he does not start by giving us a legalistic list of "dos and don'ts".  Rather, Peter instructs us to "fix" the way we think as the basis of our walk with Jesus Christ.  Clearly, controlling and directing one's innermost thoughts in a consistently Christian way that keeps the truth in mind in all that we do is not the stuff of spiritual immaturity.  Successful adherence to this command, therefore, will require the believer to grow spiritually and to continue to give attention to the teaching of the Word of God even after becoming spiritually mature.  The natural mind is extremely resistant to the divine point of view; only through continued and continual "reprogramming" with the truth of the Word of God and disciplining the fleshly mind through that truth can the believer ever truly be mentally "ready for action" in spiritual terms.  The spiritual victories of all of the believers we admire in the Bible such as Abraham, David and Daniel are the result not only of faith on the occasion of their victories but of faithfulness in believing the truth until it became an absolutely integral part of "who they were", and are also a result of consistently applying that truth in all of their innermost thoughts and meditations, especially when trouble arose (Ps.1:2).

So stand your ground, having girded your loins with truth and having put on the breastplate of righteousness.
Ephesians 6:14

Paul uses the same essential Greek verb here for "girding" (the prefix only is different) in order to express the common Greek idea that "getting dressed" essentially consists in putting one's belt around one's waist so as to order, arrange and secure one's clothing.  In spiritual terms, then, "girding" oneself means getting ready for action, as opposed to be unprepared – as in the case of someone who has not yet even gotten out of bed so as to get dressed and ready for the day.  It should come as no surprise, therefore, that being "awake" and "wakefully alert" are similar commands found in scripture used to express this same idea of spiritual preparation in one's heart through the growth that comes from hearing, learning, believing and meditating on the truth of the Word of God (Matt.24:42-43; 25:1-13; 26:41; Mk.13:33-37; 14:38; Lk.12:35-37; 21:36; 22:40; 22:46; Acts 20:31; 1Cor.16:13; Eph.5:14; 6:18; Col.4:2; 1Thes.5:6; 1Pet.4:7; 5:8; Rev.3:2; 16:15).  Failing to abide by this command, a command only capable of being fulfilled by those who have been consistent in seeking the truth and treasuring it in their hearts, means being unprepared for what the Lord sends our way, found "naked" and "asleep" instead when the time of testing comes.

Behold, He (i.e., our Lord Jesus) is coming like a thief.  Happy is he who both stays awake and guards his clothing, in order that he may not walk about naked and [people] see his shame.
Revelation 16:15

The "loins of our mind" are therefore the inner-workings of our heart, the place where the physical mind and the human spirit come together, the place where we think and feel and contemplate, the place where we "are who we are" deep inside.  Preparing our inner-person thus requires a fundamental reprogramming of the old ways of thinking we inherited before salvation.  Even if we have been saved a long time, this process of rebuilding and reforming the way we think about everything in this world is one that will never end short of kingdom-come.  The world, its viewpoint and its pressures, is ever-present, so there will always be room for improvement on this score as our "divine viewpoint" is constantly being tested.  Sadly, for the vast majority of Christians in our present Church era of Laodicea this "room for improvement" is vast because so little genuine spiritual growth is taking place in our time – because so little truth is being taught in any depth.  

"Behold, days are coming", says the Lord, "when I shall send a famine upon the earth. Not a famine of bread nor a drought of water but [a dearth] of hearing the words of the Lord. [Men] will stagger from sea to sea, and will wander from the north to the east to seek the Word of the Lord, but they will not find [it]".
Amos 8:11 

At salvation, we are given a new, cleansed heart (Ezek.36:26; Heb.10:22), a new "mind-set" or "way of thinking", as John puts it (1Jn.5:20), and with the ministry of the Holy Spirit every believer when born again experiences the joy of this new perspective as our eyes are first opened to the truth and the world is revealed for what it truly is.  We were blind before, but now we see (Jn.9:25; 9:39).1  This initial epiphany will not, however, carry the believer safely through to the end.  Our reborn heart must be continually fed with the truth – and we have to believe and treasure that truth – in order for that salvation-perspective to grow and not wither.

And we know that the Son of God has come and has given us a heart for coming to know the truth (i.e., internal perceptual change).  And we are in [the One who is] the Truth, even in [God's] Son Jesus Christ (i.e., invisible positional change).  This One is the true God and eternal life.
1st John 5:20

We have studied "virtue thinking" previously2, and the techniques for reorienting our thinking after being born again through the process of spiritual growth and progress in the application of truth.3  What is important to note here is that once we have learned enough truth and made it our own and available for the Holy Spirit's use through believing it, we still must take that further step of repeatedly "girding our [mental] loins".  This process of recalling and remembering and applying the truth, specifically and in terms of general principles, will, in the process of growth, become automatic to a degree, but we will always need to be ready to "encourage ourselves in the Lord", as David did (e.g., 1Sam.30:6), when hard times fall unexpectedly upon us (Eccl.9:12):

(4) Rejoice in the Lord all the time!  I will say it again, rejoice!  (5) Let your reasonableness be known to all men – the Lord is near.  (6) Don't worry about anything, but in everything let your requests be made known to God in prayer and in petition with thanksgiving,  (7) and [then] the peace of God which surpasses every thought will guard your hearts and your minds in Christ Jesus.  (8) So as you go forward, brothers, [keep meditating on] all the many [wonderful things you have learned], things that are true, godly, righteous, holy, pleasing [to God], reverent – if you have [developed] any virtues [in your Christian walk] and if you have [any hope of] praise [from God at the judgment] – these are the things you should be thinking about.  (9) [All these same things] which you have learned, and have received [into your hearts by believing them], and have heard about and observed me [doing in my walk], go do likewise (i.e., grow, progress, produce).  Then the God of peace will be with you.
Philippians 4:4-9

To some degree the overflowing of our faith, hope and love in the power of the Holy Spirit will happen, will grow, automatically as we advance spiritually, "growing through the grace and knowledge of our Lord and Savior, Jesus Christ" (2Pet.3:18).  But even in the passage cited directly above, although by all indications Paul is addressing a congregation composed of spiritual mature and exceptional believers, he still feels the need to make use of multiple imperatives on this score:  "rejoice!" (v. 4, twice); "show your reasonableness . . . in contemplation of the Lord's return!" (v.5); keep praying . . . so that you may have inner peace! (v.6); "think on these things! (v.7)"; "put these things into practice!" (v.8).  If the process of adopting the correct spiritual mind-set were wholly automatic or entirely second nature, so many commands would doubtless not be necessary.  As it is, fulfilling the similar command to "gird up the loins of our minds" requires spiritual growth, practice (to the point of becoming a good habit), and persistence in initiating and reinitiating it whenever necessary – and all this will be necessary on at least a daily basis.  It is for this reason that Peter makes such a point of the necessity of getting and staying on spiritual alert in one's heart and mind, precisely because it can be a bit of a struggle – because the flesh naturally resists having any spiritual viewpoint imposed upon it, while the world with its evil ruler is all too eager to lure us back to fleshly thinking with its many siren songs.  Blessedly, however, we believers all have the Holy Spirit as our ally in this struggle for dominance in what we think:

 (5) Those who are oriented to the flesh think about the things of the flesh, but those who are orientated to the Spirit, the things of the Spirit.  (6) For the thought-pattern of the flesh results in death, but the thought-pattern of the Spirit results in life and peace.  (7) Now the thought-pattern of the flesh is [one of] enmity towards God, for it does not obey God's law, nor is it [even] able [to do so].  (8) And [so] those who are under the control of the flesh (i.e., unbelievers enslaved to the sin nature) are not able to please God.  (9) But you are not under the control of the flesh, but under the control of the Spirit – if indeed the Spirit of God dwells in you.  And if anyone does not have the Spirit of Christ, that person does not belong to Him.
Romans 8:5-9

(16) But I tell you, walk in the Spirit and you will not carry out what the flesh lusts for. (17) For what the flesh lusts for is contrary to the Spirit's will, and the Spirit is opposed to what the flesh lusts for. Since these are diametrically opposed to each other in this way, what you are doing is not what you yourself choose.  (18) But if you are led by the Spirit, you are not under the Law.  (19) The acts of the sinful nature are obvious: sexual immorality, impurity and debauchery; (20) idolatry and witchcraft; hatred, discord, jealousy, fits of rage, selfish ambition, dissensions, factions and envy; (21) drunkenness, orgies – and whatever is similar to all these things.  I warn you, as I did before, that those who live like this will not inherit the kingdom of heaven.  (22) But the fruit of the Spirit is love, joy, peace, patience, kindness, uprightness, faith, (23) humility, self-control. Against such things, there is no Law.  (24) Now those who belong to Christ Jesus have crucified the flesh with its weaknesses and its lusts.  (25) If we live because of the Spirit, let us also walk by means of the Spirit.
Galatians 5:16-25

Having one's heart and mind "girded" means being ready by way of both training and preparation for whatever may come.  Just as we get ready to face the day in a physical sense, so Peter tells us we must get ready in a spiritual sense.  That preparation is both prior and immediate.  Just as we cannot get dressed for work on a given morning unless we have done some prior preparation (buying the proper suit, having it dry-cleaned when necessary, polishing our shoes, doing our laundry, etc.), so we cannot expect to be able to fulfill this spiritual command at the moment when testing or trials come upon us unless we have previously taken pains to learn God's truth so as to grow and garner the necessary spiritual inner-strength that comes from believing that truth necessary to be equal to the challenge.  And just as a wardrobe full of excellent clothing still needs to actually be put on when the work day arrives, so also our fulfillment of this command requires a day by day, moment by moment actual application of the truth from our hearts as well:  as Christians we have to be ready to "gird for the fight" at all times, because our adversary the devil is ever on the prowl, on the lookout for those who are ill-prepared for an attack, whether that lack of preparation is chronic or whether he finds us with our guard down only momentarily.  The spiritual fight we are in – and will be in every moment of every day until our Lord returns – requires that we be ever ready to "gird up" at a moments notice, whenever the evil one and his minions attack.  Fulfilling this mandate is incredibly important.  We are being watched, as Hebrews chapter eleven tells, by a great cloud of witnesses, not to mention that we are also being observed by angels (as we have just seen in the preceding verse: 1Pet.1:12), not to mention our dear Lord Jesus!  As in any fight on any battlefield, victory in battle is good for morale, but any defeat tends to deject even the bravest and best trained warriors.  But how do we go about "girding" for the fight?

The answer to this question is twofold.  First, just as every army in the field must resupply whenever time permits, so also to be fully prepared for the tribulation of this life believers need to take every opportunity to learn, believe and apply the Word of God, for the truth of scripture is the ammunition we need to fight this fight.  So the first answer to the question "how?" is to keep listening to, learning and believing the truth from a good, solid, trusted, orthodox source at every opportunity.  Second, once the believer has learned enough to be beyond the stage of "basic training", the Lord inevitably gives that believer opportunities in life to apply what has been learned and believed.  It is probably safe to say that not a day will go by in our Christian lives wherein we will not have opportunities for applying the truth to what we face in our walk through the world (even if, blessedly, major tests are not a daily occurrence).  These tests, even the minor ones, tend to make the difference between merely "having a belt" (having learned and believed a good deal of truth) and actually "girding it on" (being ready to apply it and actually doing so effectively) very clear indeed.  Whether caught off-guard or attacked when ready, in either case believers must master the technique of marshaling the truth they have come to know and believe in defense of their spiritual position whenever unexpected pressures arise.  

(1) Therefore since you have been resurrected [positionally] with Christ, keep seeking after the things above, where Christ is, seated at the right hand of God.  (2) Keep thinking on the things above, and not the things on the earth.
Colossians 3:1-2

As should be obvious in considering this quotation, keeping the divine perspective requires some effort.  If we automatically "kept thinking" about the wonders of heaven, the glories of our Lord, the fantastic things that God has done for us, is doing for us, and will do for us – in His great and matchless love – then there would be no need for Paul to command us here to do so.  Simply put, keeping in mind the wonderful doctrines and truths we have learned from the Word through individual Bible reading and formal study requires something from us beyond the initial learning and believing of these truths:  it requires consistency and care in deliberately and resolutely recovering these truths and meditating on them as we walk through this world every day and step of the way, so that we may be ready to face any crisis with the "sword of truth" (Eph.6:17).

So as you go forward, brothers, [keep meditating on] all the many [wonderful things you have learned], things that are true, godly, righteous, holy, pleasing [to God], reverent – if you have [developed] any virtues [in your Christian walk] and if you have [any hope of] praise [from God at the judgment] – these are things you should be thinking about. 
Philippians 4:8

Beyond telling us that we should do so, scripture does not tell us precisely how to do so.  Such things are (rightly and blessedly) left to our individual application of the truth.  One thing we can say for certain is that it is the Lord Jesus Christ who embodies all the truth we know and love, and that it is He who should be the focal point of all our efforts in this regard.

(14) For this reason I bow my knees to the Father, (15) from whom His entire family in heaven and on earth has received its name, (16) that He may grant you according to the riches of His glory to be powerfully strengthened in your inner person through His Spirit, (17) so that, rooted and grounded in love, Christ may dwell in your hearts through faith, (18) so that you may be able to comprehend with all saints what is the breadth and length and depth and height [of His love for you], (19) [that is], so that you may know the love of Christ which outstrips [human] understanding [in every way], and so that you may be filled up [to the brim] with the entire "fullness" of God.
Ephesians 3:14-19

For to me, to live is Christ, and to die is gain.
Philippians 1:21

[Moses] grew strong by seeing the One who cannot be seen (i.e., by keeping his mind's eye on the invisible Lord Jesus Christ).
Hebrews 11:-27b

Remembering key verses and psalms and calling them ever to mind, repeatedly reading and rereading our Bibles at every opportunity, contemplating our Lord and the truths He embodies as the Word of God incarnate, and keeping up a constant dialogue with the One we love so much through the great opportunity of continual prayer are all wonderful ways to put the above into practice, to set ourselves to fulfilling the mandate of "girding up" our thoughts and emotions for service to our Lord.  Additionally, it is certainly true that there is value in developing a personal list of good things to remember which in particular relate to the specific command of "girding up" for the spiritual combat that ofttimes comes upon us unexpectedly.  This may include, for example, remembering what the Lord has done for others (as in rescuing the Israelites at the Red Sea; cf. Josh.24:6; Neh.9:9; Ps.106:9; 136:13; Acts 7:36; Heb.11:29), and conjoining that remembrance with a like remembrance of the great deliverances He has wrought for us in our own lives and in the lives of those we love.  When we experience the encouragement the Spirit is wont to give us in times of trouble (2Cor.1:3-7), the passages, verses, examples and truths He uses to encourage us are also very worthwhile to hold onto, in order to deploy them in support of our embattled emotions whenever in future we receive a shock or a surprise attack from the evil one (as we are sure to do).  The following list is not meant to be taken as dogmatic or anything approaching complete, but the points included may perhaps prove helpful to the reader in times of stress – as they have proved helpful to the author:

Remember:  Jesus is holding us by the hand (Jn.10:28-29; cf. Deut.33:27).

(23) Yet I am always with you; you hold me by my right hand.  (24) You guide me with your counsel, and afterward you will take me into glory.
Psalm 73:23-24 NIV

Remember:  Jesus is with us in the storm (Ps.107:29; Prov.10:25).

(24) Suddenly a furious storm came up on the lake, so that the waves swept over the boat. But Jesus was sleeping. (25) The disciples went and woke him, saying, "Lord, save us! We’re going to drown!" (26) He replied, "You of little faith, why are you so afraid?" Then he got up and rebuked the winds and the waves, and it was completely calm.
Matthew 8:24-26 NIV

Remember:  Jesus is leading us across the stormy waters (Ps.66:12).

(26) When the disciples saw him walking on the lake, they were terrified. "It’s a ghost," they said, and cried out in fear.  (27) But Jesus immediately said to them: "Take courage! It is I. Don’t be afraid." (28) "Lord, if it’s you," Peter replied, "tell me to come to you on the water." (29) "Come," he said. Then Peter got down out of the boat, walked on the water and came toward Jesus. (30) But when he saw the wind, he was afraid and, beginning to sink, cried out, "Lord, save me!" (31) Immediately Jesus reached out his hand and caught him. "You of little faith," he said, "why did you doubt?"
Matthew 14:26-31 NIV

Remember:  God has arranged and our Lord Jesus is working out everything that happens for our absolute good (Rom.8:29-31; Eph.1:7-14).

And we know that, for those who love God, He works everything together for good – [that is to say,] for those who have been called according to His plan.
Romans 8:28

Remember:  Jesus is pleased with us when we believe the truth rather than what we see (2Cor.4:18; 5:7).

(1) It is faith [in the Living and written Word], moreover, that substantiates what we hope for.  [Faith] provides proof of things unseen.  (2) For it is by this [very faith] that believers of old received their divine approval.
Hebrews 11:1-2

Remember:  Jesus is carrying out God's will for us for the good in every way so that we may rejoice even when things surprise or upset us.
	
(16) Rejoice always, (17) give thanks in all circumstances; (18) for this is God’s will for you in Christ Jesus.
1st Thessalonians 5:16-18 NIV

Rejoice in the Lord always. I will say it again: Rejoice!
Philippians 4:4 NIV

(2) Brothers, when you are being beset with all manner of trials, take pains to be joyful.  (3) For you should keep in mind that this testing of your faith develops perseverance.  (4) So let your perseverance develop fully, that you may become fully mature and entitled to a full reward, having been found lacking in no respect.
James 1:2-4

Remember:  Our hearts are a temple where we fellowship with the Lord Jesus, and as such are worthy of being cleansed and defended against all profane intrusion (cf. Jer.17:9).

Jesus replied, "Anyone who loves me will obey my teaching. My Father will love them, and we will come to them and make our home with them."
John 14:23 NIV

Remember:  Jesus is pleased with the smallest amount of faith from us, since a small seed can grow into a large tree of faith, and the smallest faith can move mountains (Matt.13:31-32).

"Truly I tell you, if you have faith as small as a mustard seed, you can say to this mountain, 'Move from here to there,' and it will move. Nothing will be impossible for you."
Matthew 17:20b NIV

Remember:  We may be weak, but Jesus is strong, and He makes our weakness into the greatest strength because we are leaning on Him and not on ourselves (2Cor.11:30; Heb.11:34).

But he said to me, "My grace is sufficient for you, for my power is made perfect in weakness." Therefore I will boast all the more gladly about my weaknesses, so that Christ's power may rest on me.
2nd Corinthians 12:9 NIV

Remember:  Even though we walk through the valley of deepest darkness, Jesus is with us and will soon turn our darkness into the light for which we long.
Yea, though I walk through the valley of the shadow of death, I will fear no evil; For You are with me; Your rod and Your staff, they comfort me.
Psalm 23:4 NKJV

Yet I am writing you a new command; its truth is seen in him and in you, because the darkness is passing and the true light is already shining.
1st John 2:8 NIV

Remember:  Jesus is for us, not against us, so all attacks that come our way are not from Him but from the evil one, and He will protect us.

If anyone does attack you, it will not be my doing; whoever attacks you will surrender to you.	
Isaiah 54:15 NIV

And don't bring us into testing [that we can't handle] but deliver us from the evil one.
Matthew 6:13

For our battle is not against flesh and blood, but against [angelic] princes, against [angelic] authorities, against the cosmic powers of this [present] darkness, against evil spirits in the heavenly realms.
Ephesians 6:12

Remember:  Jesus is the One shepherding us, even if we must pass through the valley of the death-shadow, and He will provide for us and keep us safe no matter what (Jn.10:11-16).

The Lord is the One shepherding me.  Therefore I will not be lacking [anything I need].
Psalm 23:1

Remember:  Jesus is the One conducting this battle; it's all about Him, not us, so we can rely on His deliverance no matter what.

"All those gathered here will know that it is not by sword or spear that the LORD saves; for the battle is the LORD's, and he will give all of you into our hands."
1st Samuel 17:47 NIV

Be strong and courageous, do not be afraid or tremble at them, for the LORD your God is the one who goes with you.  He will not fail you or forsake you.
Deuteronomy 31:6 NASB

There is so much more that could be said – perhaps quoting the entire Bible, fully explained and rightly understood.  The main thing to remember is that God is in complete control, and that as those who belong to Jesus Christ we have nothing to fear:  it's all about Jesus Christ, "in whom are hidden all the treasures of wisdom and knowledge" (Col.2:3 NASB).

Spiritual Alertness:  The phrase translated "in spiritually mature alertness" is based on a Greek participle (from the verb nepho) being used circumstantially here.  That is to say, "being alert" is the circumstance which should qualify or condition the "girding up of the loins of our minds" as Peter expresses it in verse thirteen of chapter one.  Peter combines these two ideas to make it clear that "girding up" or preparing ourselves for spiritual warfare is both a synchronic and a diachronic task – that is, we not only have to be ready to orient ourselves spiritually at any given time but we also must already have prepared ourselves ahead of time through daily spiritual growth in order to be able meet the challenges that will come upon us.  Adding this participle, translated by many versions with the use of the English word "sober" (e.g., KJV: "be sober"; ESV: "being sober-minded"), makes it clear that we need to be on the spiritual alert at all times.  If we are – and if we are already trained for spiritual warfare through growth in the Lord – then we stand a much better chance of "girding up" our minds for spiritual combat when pressures come suddenly upon us.  "Sobriety" is not a bad translation for nepho, but in addition to the very literal meaning of "not being drunk with alcohol", the verb also means "to be wakeful" and "to be alert" generally, and it is very clear that while alcohol is a problem for many Christians, it is certainly not the only nor even usually the most significant impediment to being on guard against the tricks and traps of the evil one.  

It is very difficult to be 100% alert at all times, in any sphere of life.  Even if a soldier stays awake on guard and at his post, there is no guarantee that he will maintain an adequate level of alertness to notice the enemy sneaking up on his position.  For Christians, the situation is even more difficult – and even more important.  It is not uncommon for us to find ourselves walking very close to the Lord in great peace and joy as a result of winning some spiritual battle and/or learning and appreciating some spiritual truth . . . and then to slip back into a measure of worldly thinking.  This is not necessarily even sinful, but given the fact that we have sin natures, are surrounded by the noise and distractions of the world, have complications and intricacies of life that compete for our attention, it is no uncommon thing to find ourselves, even in spiritual maturity when our spiritual momentum is excellent, becoming distracted in our hearts – if only momentarily – from the truths that we know in our heart of hearts are the most important.  The problem is that even a momentary lapse on "guard duty" can result in being vulnerable to a nasty surprise attack – and the devil is a past master of surprise attacks:
 
Be sober (nepho), be vigilant; because your adversary the devil walks about like a roaring lion, seeking whom he may devour.
1st Peter 5:8 NKJV

Mature believers who make a practice of preparing themselves for battle by learning the truth, believing it and applying it consistently, are less likely to be seriously compromised even if they have let their guard down momentarily.  No one is perfect, not even the most spiritually advanced, so that the techniques discussed earlier in this study – along with the "tactics" we each personally develop to help us reorient to the truth and readjust our emotions when trouble arises – are needful whenever we are caught by surprise.  But those who are indeed walking closely with the Lord will find recovery easier and in a way which is more "second nature", while those who are sporadic in their approach to the truth, both in taking it in and in meditating on it after the fact, will find life's pressures more spiritually problematic – while those who are wandering spiritually will find the "roaring lion" tracking them at every turn.

(18) And don't get drunk with wine – which is dissipating – but instead keep on being ful-filled (i.e., making progress in spiritual growth) by means of the Holy Spirit (i.e., the means to edification in contrast to dissipation).  (19) [Be] speaking [encouragement] to your own selves through psalms, and hymns, and spiritual songs, singing and vocalizing psalms in your heart to the Lord, (20) giving thanks at all times for everything in the Name of our Lord to God our Father.
Ephesians 5:18-20

(15) And let the peace [which comes] from Jesus Christ be the referee of your hearts [of what and how to think]: this is the peace to which you have [all] been called in one Body.  And be thankful!  (16) Let the Word of the Lord dwell in you richly, teaching and admonishing your own selves [individually] in all wisdom, [and] with psalms, and hymns and spiritual songs, singing in your hearts to God.  (17) And whatever you do in word or in deed, doing everything in the Name of the Lord Jesus, giving thanks to God the Father through Him.
Colossians 3:16-17

Being able to "gird up the loins of your mind in spiritually mature alertness" thus requires prior spiritual training, readiness to orient oneself to the spiritual pressures which come, and the actual "doing" of putting on (and keeping on) the "whole armor of God" as we fight our way forward up the high road to Zion for our Commander, Jesus Christ.

Endure hardship with me like a good soldier of Christ Jesus. No one on military campaign becomes involved in the affairs of normal life. [He avoids such things] that he may please the one who enlisted him.
2nd Timothy 2:3-4

(11) Put on the full armor of God, so that you can take your stand against the devil’s schemes.  (12) For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms.  (13) Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand.  (14) Stand firm then, with the belt of truth buckled around your waist, with the breastplate of righteousness in place, (15) and with your feet fitted with the readiness that comes from the gospel of peace.  (16) In addition to all this, take up the shield of faith, with which you can extinguish all the flaming arrows of the evil one.  (17) Take the helmet of salvation and the sword of the Spirit, which is the word of God.
Ephesians 6:11-17 NIV

Fight the good fight of faith.
1st Timothy 6:12a

I give you this command, Timothy my child, in accordance with the prophecies that were made long ago about you, that you conduct a good [spiritual] campaign, one that is in keeping with them.
1st Timothy 1:18

I have fought the good fight. I have completed my course. I have kept the faith.
2nd Timothy 4:7

Set your Hope upon the Grace to Come:

The "revelation of Jesus Christ" refers to His return to the world in glory to take up His crown and establish His kingdom at the second advent.  On that glorious day to come, we believers, whether still alive on this earth or awaiting that great day in His presence in heaven, will be resurrected one and all, with the "dead in Christ" rising first, then "we who are alive" being transformed without physical death to rise in resurrection "to meet the Lord in the air" (1Thes.4:15-17).  That is the "blessed hope" to which all Christians should aspire and to which we should be looking at all times.

[W]e who are awaiting the blessed hope, namely the epiphany of the glory of our great God and Savior, Jesus Christ (i.e., when we too will be resurrected in glory when He appears).
Titus 2:13

As reborn believers in Jesus Christ, we are all recipients of the "multifarious grace of God" (1Pet.4:10).  For of the "fullness" of Christ, we have all received "grace upon grace" (Jn.1:16).  Grace is God's good favor, and what greater favor from God can be imagined than having death turned into life eternal through the sacrifice of His dear Son for our sins?  The cross is "grace", and is the beginning of all the favor we receive from God after we believe.  In this present world, we do still have "tribulation" (Jn.16:33), but in the life to come, there will be no sin, no death, no evil to impede the as yet truly unimaginable outpouring of grace that will be ours on that great day to come as members of Christ's Church.

But as it is written: "Eye has not seen, nor ear heard, nor have entered into the heart of man the things which God has prepared for those who love Him." 
1st Corinthians 2:9

How, then, do we "set our hope" on the blessings to come?  Simply put, this is a matter first of learning all we can – everything scriptural, that is – about the glories ahead.  This includes the teachings about the resurrection and everything found in scripture about our eternal rewards and our inheritance in the New Jerusalem.4  But in addition to learning and believing these truths, we also have to be ready to apply these truths to our day to day situation.  And, indeed, remembering that we have an incorruptible body awaiting us "eternal in the heavens" (2Cor.5:1), and an eternal reward stored up for us in heaven "where neither moth nor rust destroys, and where thieves do not break in or steal" (Matt.6:20 NASB) is extremely encouraging, especially when we are feeling physical pain or material deprivation in this brief life, for this hope of reward and resurrection is a legitimate and necessary focus of all Christian faith as it is applied in the "battlefield thinking" we must develop to prosper in the spiritual warfare in which we are all involved:

Now without faith, it is impossible to please [God].  For whoever wishes to draw nearer to God must believe that He exists, and that He will reward those who earnestly seek Him.
Hebrews 11:6

(3) May the God and Father of our Lord Jesus Christ be praised, who has in His great mercy caused us to be reborn to a hope which lives through Jesus Christ's resurrection from the dead, (4) and to an inheritance which will never be destroyed, defiled, or dimmed, but which is being guarded in heaven for us.
1st Peter 1:3-4

In other words, "setting our hope" on the glories to come when our Lord returns is an example of "girding up our minds" in spiritual alertness.  Focusing on the blessings of our eternal tomorrow is an essential part of how every advancing Christian gets through "today", "as long as it is called 'Today' " (Heb.3:13; cf. Ps.118:24), because while the evil one may have little or only marginal interest in believers who are going sideways or backwards, we may be sure that genuine spiritual advance always provokes serious opposition.  God has given us the truth we need (the entire Bible, in fact), the power we need (the indwelling of God the Holy Spirit), and the techniques we need (mentally "girding up" to apply those truths through the Spirit).  All that is needed is for us to actually make use of these blessed resources in the cause of Jesus Christ.  

(4) For the weapons of our warfare are not fleshly, but are powerful for God, for the destruction of strongholds, (5) destroying sophistries and every presumption that raises itself up against the knowledge of God, and taking every thought prisoner so as to obey Christ, (6) being ready to reprove every disobedient thought once you have come into the fulness of mature obedience [in respect to guarding your thoughts].
2nd Corinthians 10:4-6

It is a serious and mortal warfare in which we are involved, a "spiritual warfare" in which our weapons are not the weapons of this world, but the weapons of the truth, the Spirit, and the techniques of putting these together in combating whatever lies, whatever pressures, whatever disasters, whatever uncertainties may come our way in this life (and come they shall).  That is to say, it is all about our faith in the truth, learning it (by doing our own due diligence in paying attention to sound Bible teaching), believing it (whereby the Spirit makes it usable for us), and applying it to whatever we may face in this life like the powerful sword it is, inspired, made real, and empowered by the Holy Spirit:

And [in this spiritual warfare] put on the helmet of salvation and gird on the sword of the Spirit – which is the Word of truth.
Ephesians 6:17 (cf. Heb.4:12)

This "girding up" and "staying alert" and "setting our hope" is really the only way to maintain our spiritual momentum for Jesus Christ in this life, the only valid way to overcome for Him in the suffering, trials, tests and tribulations to which all advancing will be subjected.  The fight may seem daunting at times, but we need to remember that our Lord has already won the victory, and we are merely making use of the spoils He has won so as to come into our share of the great reward ahead – provided we enter into that victory through courageously fighting the good fight of faith.

In this world you do have tribulation. But be courageous.  I have overcome the world.
John 16:33

For everything that has been born from God overcomes the world.  And this is the victory that has overcome the world: our faith [in Christ]!
1st John 5:4 (cf. v.1)

(26) And to the one who wins the victory and gives heed to My works until the end, I will give to him authority over the nations.  (27) And he will shepherd them with an iron rod and crush them like vessels of clay, just as I have received [the authority] from My Father.
Revelation 2:26-27