1 Corinthians 7:13-17

And if any woman has an unbelieving husband, and he consents to live with her, she must not divorce her husband.

For the unbelieving husband is sanctified through his wife, and the unbelieving wife is sanctified through her believing husband; for otherwise your children are unclean, but now they are holy.

Yet if the unbelieving one is leaving, let him leave; the brother or the sister is not under bondage in such cases, but God has called us in peace.

For how do you know, wife, whether you will save your husband? Or how do you know, husband, whether you will save your wife?

Only, as the Lord has assigned to each one, as God has called each, in this way let him walk. And so I direct in all the churches.