Genesis 38:9-10 - Exposition

And Onan knew that the seed should not be his; and it came to pass, when —literally, and it was if, i.e. whenever— he went in unto his brother's wife, that he spilled it on the ground (literally, destroyed to the ground ) , lest that he should (or, so as not to) give seed to his brother. And the thing which he did displeased (literally, was evil in the eyes of ) the Lord :—the word Jehovah is employed not because the writer was a late interpolator, but because the sin of Onan was an offence against the sanctity and prosperity of the theocratic family (Hengstenberg)— wherefore he ( i.e. Jehovah) slew him also ( vide supra ).