They've also said that Joseph fought against the advances of Potipher's wife because he knew of God's standards for marriage to only be that of one man and one woman.
Let's review.
Abraham -- at least 2 wives, Sarah & Hagar.
Isaac -- (I only know of Rebecca)
Jacob -- Rachael, Leah, both of their female servants (at least 4)
Joseph had amazing examples on monogamy.
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