I Corinthians 7:12-18

But to the rest I, not the Lord, say: If any brother has a wife who does not believe, and she is willing to live with him, let him not divorce her. And a woman who has a husband who does not believe, if he is willing to live with her, let her not divorce him. For the unbelieving husband is sanctified by the wife, and the unbelieving wife is sanctified by the husband; otherwise your children would be unclean, but now they are holy. But if the unbeliever departs, let him depart; a brother or a sister is not under bondage in such cases. But God has called us to peace. For how do you know, O wife, whether you will save your husband? Or how do you know, O husband, whether you will save your wife? But as God has distributed to each one, as the Lord has called each one, so let him walk. And so I ordain in all the churches. Was anyone called while circumcised? Let him not become uncircumcised. Was anyone called while uncircumcised? Let him not be circumcised.