Genesis 2:24

24 aTherefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh.

Matthew 19:6

6So they are no longer two but one flesh. bWhat therefore God has joined together, let not man separate.”

1 Corinthians 7:10

10To the married cI give this charge (not I, but the Lord): dthe wife should not separate from her husband
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