Mark 10:8

New American Bible - revised edition

and the two shall become one flesh.’ So they are no longer two but one flesh.

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That is why a man leaves his father and mother and clings to his wife, and the two of them become one body.

Therefore what God has joined together, no human being must separate.”

[Or] do you not know that anyone who joins himself to a prostitute becomes one body with her? For “the two,” it says, “will become one flesh.”

So [also] husbands should love their wives as their own bodies. He who loves his wife loves himself.