The Lord will not be willing to forgive him, but rather the anger of the Lord and his jealousy will smoke against that man, and the curses written in this book will settle upon him, and the Lord will blot out his name from under heaven.
But Onan knew that the offspring would not be his. So whenever he went in to his brother’s wife he would waste the semen on the ground, so as not to give offspring to his brother.