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Genesis 2:24
Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh.
St. Matthew 19:4,5,6
And he answered and said unto them, Have ye not read, that he which made them at the beginning made them male and female,
And said, for this cause shall a man leave father and mother, and shall cleave to his wife: and they twain shall be one flesh?
Wherefore they are no more twain, but one flesh. What therefore God hath joined together, let not man put asunder.