Just for the record, Onanism (the so-called "sin" of masturbation) is not about masturbation. Tamar was, frankly, a hot babe. Later in the story she had no problem passing as a Temple prostitute. Onan was required to marry her, his sister-in-law, when she was childless when Onan's brother did something that made god open a whole in the ground and swallow him. So Onan wanted to "tap that" in the worst way, but did NOT want to have a child who would be legally his older brother's child in the rules of inheritance. The sin is schtupping someone while violating the implicit and explicit promises involved in two people opening up totally to each other.

Obviously designed to stop you committing sins that you would not have thought were sins. It would have been nice to have them listed as the Additional 13 Commandments.

Well damn, I'm a huge sinner then.

In my experience, most religious people use the Bible as a showy centerpiece, not something to read. I’ve also noted that atheists who have converted from Christianity usually have a much higher knowledge of the Bible than Christians. Atheists who have grown up in secular households usually don’t care and have very little knowledge.