Scriptures

⁹ And Onan knew that the seed should not be his; and it came to pass, when he went in unto his brother's wife, that he spilled it on the ground, lest that he should give seed to his brother.

⁹ But Onan was not willing to have a child who would not be his own heir. So whenever he had intercourse with his brother’s wife, he spilled the semen on the ground. This prevented her from having a child who would belong to his brother.

⁹ Onan knew that the offspring would not be his; so when he went in to his brother’s wife, he wasted his seed on the ground in order not to give offspring to his brother.

⁹ But Onan knew that the heir would not be his; and it came to pass, when he went in to his brother’s wife, that he emitted on the ground, lest he should give an heir to his brother.