38:9 But Onan knew that the child16 would not be considered his.17 So whenever18 he had sexual relations with19 his brother’s wife, he withdrew prematurely20 so as not to give his brother a descendant.
tnHeb “would not be his,” that is, legally speaking. Under the levirate system the child would be legally considered the child of his deceased brother.
18
tn The construction shows that this was a repeated practice and not merely one action.
sn The text makes it clear that the purpose of the custom was to produce an heir for the deceased brother. Onan had no intention of doing that. But he would have sex with the girl as much as he wished. He was willing to use the law to gratify his desires, but was not willing to do the responsible thing.
19
tnHeb “he went to.” This expression is a euphemism for sexual intercourse.
20
tnHeb “he spoiled [his semen] to the ground.” Onan withdrew prematurely and ejaculated on the ground to prevent his brother’s widow from becoming pregnant.