Actually, the whole New Testament assumes one man and one woman. "The two shall become one"
"Actually, the whole New Testament assumes one man and one woman. "The two shall become one"
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That's one way to look at it. However, that was not always the case in New Testament times. And multiple wives were never condemned in the New Testament. There's no indication that it was a sin to have multiple wives, although it was certainly a sin to commit adultery. The prohibition against polygyny came later.