Hebrews 13:4
Marriage is honorable in all, and the bed undefiled: but fornicators and adulterers God will judge.
Topicalbible.org—AKJV

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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Genesis 2:24
Therefore shall a man leave his father and his mother, and shall join to his wife: and they shall be one flesh.
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