What's the Punishment for Not Obedience to the Leviate Law?

Onan is tasked by the leviate law of Judah around 25 to raise up seed and when he goes into his sister-in-law, the scripture says he spilled his seed on the ground. And so my buddy tells me, Tim, that's a contraceptive act. And what was the punishment? He was killed. So I got some Protestant commentaries and such. The Protestant line in many of the commentaries is, well, that wasn't a contraceptive act,. It was an act of disobedience against the leviated law of Judas around me 25. That's why he was put to death, not for contraception. But you know what Matt's response is? Well,