1 Corinthians 7:12-18

For all the others I say this (I am saying this, not the Lord): If a Christian man has a wife who is not a believer, and she is happy to live with him, he must not divorce her. And if a Christian woman has a husband who is not a believer, and he is happy to live with her, she must not divorce him. The husband who is not a believer is made holy through his believing wife. And the wife who is not a believer is made holy through her believing husband. If this were not true, your children would not be clean, but now your children are holy. But if those who are not believers decide to leave, let them leave. When this happens, the Christian man or woman is free. But God called us to live in peace. Wife, you don’t know; maybe you will save your husband. And husband, you don’t know; maybe you will save your wife. But in any case each one of you should continue to live the way God has given you to live—the way you were when God called you. This is a rule I make in all the churches. If a man was already circumcised when he was called, he should not undo his circumcision. If a man was without circumcision when he was called, he should not be circumcised.