Contradiction with Leviticus 18:18
Prohibits marrying a wife's sister while the wife is still alive and in her lifetime.
Leviticus 18:18: Neither shalt thou take a wife to her sister, to vex [her], to uncover her nakedness, beside the other in her life [time]. [a wife...: or, one wife to another]
Contradiction with Genesis 2:24
Suggests a union between only two people becoming one flesh, not through polygamy.
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.