He SPILLED HIS SEED ON THE GROUND trying to trick the voyeur alleged gawd Jehovah YHWH by penetrating the grieving widow but hoping the alleged creator of a 15 billion years wide universe was not looking at the semen stained dirt. ....it's not nice to break any bible rule under penalty of DEATH for having the orgasm elsewhere than the misogynistic gawd owned vagina
"Results like these do not belong on the résumé of a Supreme Being. This is the kind of shit you'd expect from an office temp with a bad attitude. (George Carlin)
There is an even worse part of this story. Do you know why,Tamar's husband is dead in the first place? Because God decides he doesn't like him (Er was his name), Er was considered wicked in Gods eyes. Are we not all wicked in Gods eyes? (well, that's what Christians have told me all my life.) Onan didn't have a problem banging his brother's wife; he was fine doing that, he just didn't want to knock her up. If he did, according to the old testament that son isn't his son, it's Er's son. What this really shows is just how incompetent Gods is, and he's not a supreme being, he's an office temp with a bad attitude.