"Marriage of Believers and Unbelievers."
http://ichthys.com 
Question:   
Could you explain what 1st Corinthians 7:14 means? The unbelieving husband is sanctified by the wife. Is he set apart and will become a believer?   Thank you again. 
Response:
1st Corinthians 7:14 is to be understood in light of the previous verse where it says that a believing wife is not to divorce her unbelieving husband just because he is an unbeliever. Verse 14 reassures women in this difficult situation that their lives are not meaningless in the Lord, nor their children somehow tainted because of their spouse's lack of belief - their faith sanctifies the union. On the other hand, verse 15 (the verse immediately following), also makes it clear that if the unbelieving husband is not willing to continue in a marriage with a believing wife, the wife is free from the responsibility of trying to maintain a union under such impossible circumstances; she should feel no guilt about giving up when her husband has already given up because, as verse 16 goes on to say, in effect, "you can't tell whether or not [your influence and prayers] will save your husband".
We all have close friends, family, some even children and spouses, who are resistant to the gospel of Jesus Christ. This is a very hard thing and leads to many tears. On the one hand, every person has their own free will, and it is not for us to decide for them (though we wish we could in love force them to do what is in their best interest); on the other hand, we Christians should never ever underestimate the power and wisdom of God, His mercy, His love and His perfect plan; He can melt even the hardest heart of stone, and has been known to do so. 
Wives, in the same way be submissive to your husbands so that, if any of them do not believe the word, they may be won over without words by the behavior of their wives, when they see the purity and reverence of your lives.
1st Peter 3:1-2  NIV 
The best we can do is to persevere in prayer and in our daily spiritual growth from the Word of God; the closer we get to Him, the better we understand His will and the more effective our prayers become. In the end, we have faith that He will work everything out for good for us (Rom.8:28); we may not know how or when at this point, but that is part of the test and strengthening of our faith. And faith in Him is never misplaced, and, ultimately, never disappointed.
You may find the information in these other links helpful:
No grounds for divorce?
A conversation about divorce and remarriage.
Evangelism
May God give you wisdom and patience, and answer your prayers.
Yours in Christ,
Bob Luginbill
http://ichthys.com