2 Corinthians 6:14
Be you not unequally yoked together with unbelievers: for what fellowship has righteousness with unrighteousness? and what communion has light with darkness?
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1 Corinthians 6:18
Flee fornication. Every sin that a man does is without the body; but he that commits fornication sins against his own body.
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Hebrews 13:4
Marriage is honorable in all, and the bed undefiled: but fornicators and adulterers God will judge.
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