The main man in this, the big mocker, was Abraham. Not to make this too much of a scripture lesson, but it's kind of hard to understand the Jews without understanding Abraham, or Abram, as he was known before he had his big conversation with God, recorded in Genesis 17. When Abram was ninety years and nine, the Lord appeared to Abram and said unto him, I am the Almighty God, walk before me and be thou perfect. And I'm gonna make a covenant with you and a bunch of cool things will happen, like you're gonna have kids and your descendants will number the stars and you can have all the land of Canaan forever, it's gonna be awesome. I'm paraphrasing, by the way, Thought Bubble. So God promised that Abram would have kids with his wife, even though the dude was already like ninety-nine, but there was a catch. This is my covenant which ye shall keep between me and you and thy seed after thee, every man child among you shall be circumcised.