1 Corinthians 7:14

7:14 For the unbelieving husband is sanctified because of the wife, and the unbelieving wife because of her husband. Otherwise your children are unclean, but now they are holy.

1 Corinthians 15:29

15:29 Otherwise, what will those do who are baptized for the dead? If the dead are not raised at all, then why are they baptized for them?