1 Corinthians 7:12-14
To the rest I say (I, not the Lord) that if any brother has a wife who is an unbeliever, and she consents to live with him, he should not divorce her.
If any woman has a husband who is an unbeliever, and he consents to live with her, she should not divorce him.
For the unbelieving husband is made holy because of his wife, and the unbelieving wife is made holy because of her husband. i Otherwise your children would be unclean, but as it is, they are holy.
English Standard Version (ESV) The Holy Bible, English Standard Version Copyright © 2001 by Crossway Bibles, a division of Good News Publishers.
For they have taken some of their daughters to be wives for themselves and for their sons, so that the holy race has mixed itself with the peoples of the lands. And in this faithlessness the hand of the officials and chief men has been foremost.
Did he not make them one, with a portion of the Spirit in their union? And what was the one God seeking? Godly offspring. So guard yourselves in your spirit, and let none of you be faithless to the wife of your youth.