This Bible contradiction is from the Skeptic's Annotated Bible.
1 Corinthians 7:12-14 View context
But to the rest speak I, not the Lord: If any brother hath a wife that believeth not, and she be pleased to dwell with him, let him not put her away.
And the woman which hath an husband that believeth not, and if he be pleased to dwell with her, let her not leave him.
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.
No, they are unclean.
2 Corinthians 6:14-17 View context
Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?
And what concord hath Christ with Belial? or what part hath he that believeth with an infidel?
And what agreement hath the temple of God with idols? for ye are the temple of the living God; as God hath said, I will dwell in them, and walk in [them]; and I will be their God, and they shall be my people.
Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean [thing]; and I will receive you,