12 But as to the rest, I say, not the Lord, If any brother have an unbelieving wife, and she consent to dwell with him, let him not leave her. 13 And a woman who has an unbelieving husband, and he consents to dwell with her, let her not leave [her] husband. 14 For the unbelieving husband is sanctified in the wife, and the unbelieving wife is sanctified in the brother; since [otherwise] indeed your children are unclean, but now they are holy. 15 But if the unbeliever go away, let them go away; a brother or a sister is not bound in such [cases], but God has called us in peace.
Matthew Henry's Commentary on 1 Corinthians 7:12-15
Commentary on 1 Corinthians 7:10-16
(Read 1 Corinthians 7:10-16)
Man and wife must not separate for any other cause than what Christ allows. Divorce, at that time, was very common among both Jews and Gentiles, on very slight pretexts. Marriage is a Divine institution; and is an engagement for life, by God's appointment. We are bound, as much as in us lies, to live peaceably with all men, Romans 12:18, therefore to promote the peace and comfort of our nearest relatives, though unbelievers. It should be the labour and study of those who are married, to make each other as easy and happy as possible. Should a Christian desert a husband or wife, when there is opportunity to give the greatest proof of love? Stay, and labour heartily for the conversion of thy relative. In every state and relation the Lord has called us to peace; and every thing should be done to promote harmony, as far as truth and holiness will permit.