Then Judah said to Onan, “Have intercourse with your brother’s wife, in fulfillment of your duty as brother-in-law, and thus preserve your brother’s line.”
Onan, however, knew that the offspring would not be his; so whenever he had intercourse with his brother’s wife, he wasted his seed on the ground, to avoid giving offspring to his brother.
The Lord will single them out from all the tribes of Israel for doom, in keeping with all the curses of the covenant written in this book of the law. Punishment for Idolatry.