Genesis 38:4

38:4 She became pregnant again and had another son, whom she named Onan.

Genesis 38:9

38:9 But Onan knew that the child ¹  would not be considered his. ²  So whenever ³  he had sexual relations with ⁴  his brother’s wife, he withdrew prematurely ⁵  so as not to give his brother a descendant.

[38:9]  ¹ tn Heb “offspring.”

[38:9]  ² tn Heb “would not be his,” that is, legally speaking. Under the levirate system the child would be legally considered the child of his deceased brother.

[38:9]  ³ tn The construction shows that this was a repeated practice and not merely one action.

[38:9]  ⁴ tn Heb “he went to.” This expression is a euphemism for sexual intercourse.

[38:9]  ⁵ tn Heb “he spoiled [his semen] to the ground.” Onan withdrew prematurely and ejaculated on the ground to prevent his brother’s widow from becoming pregnant.