“The only thing he did different from any other married couple was, he spilled his seed. “
Incorrect. He was having sex with his brother’s wife, allowed ONLY for the purpose of giving her a child, AND spilling his seed. I think there is a difference between a married couple choosing not to have kids right now, and someone having sex with their brother’s wife under a false pretense.
Couples can seek intimacy with each other without wanting to have kids at that time. I fail to see how mutually agreeing not to have kids equals lying to each other about your love.
His widow.
Yet the Bible describes contraceptive behavior by Onan, then calls it "despicable". Surely having sex with the widow would not be despicable, since that is what the law required.
I fail to see how mutually agreeing not to have kids equals lying to each other about your love.
The decision to not have kids may or may not in itself be sinful, but if it is arrived at openly, certainly it is not deceptive. The contracepted sex, however, is a form of lying even if it is mutually decided upon as there is no union of bodies open to procreation, as married people are sworn to. Both spouses end up cheated objectively, and God's covenant of marriage is defrauded.