Leviticus 20:20

20 And if a man has sex relations with the wife of his father's brother, he has put shame on his father's brother: their sin will be on them; till the day of their death they will have no children.

Leviticus 20:20 In-Context

18 And if a man has sex relations with a woman at the time when she is unwell, he has seen her fountain and she has let the fountain of her blood be uncovered, and the two of them are to be cut off from among their people.
19 And you may not have sex connection with your mother's sister or your father's sister, for they are his near relations: their sin will be on them.
20 And if a man has sex relations with the wife of his father's brother, he has put shame on his father's brother: their sin will be on them; till the day of their death they will have no children.
21 And if a man takes his brother's wife, it is an unclean act; he has put shame on his brother; they will have no children.
22 So then, keep my rules and my decisions and do them, so that the land which I am giving you as your resting-place may not violently send you out again.
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