1 Corinthians 7:14-18

For the unbelieving husband is sanctified by the wife, and the unbelieving wife is sanctified by the husband: else were your children unclean; but now are they holy.

But if the unbelieving depart, let him depart. A brother or a sister is not under bondage in such cases: but God hath called us to peace.

For what knowest thou, O wife, whether thou shalt save thy husband? or how knowest thou, O man, whether thou shalt save thy wife?

But as God hath distributed to every man, as the Lord hath called every one, so let him walk. And so ordain I in all churches.

Is any man called being circumcised? let him not become uncircumcised. Is any called in uncircumcision? let him not be circumcised.