A little boy was confused by the differences between the Old Testament and the New Testament. "God was such a JERK back then" he said, "I mean, he had bears eat a bunch of kids because they made fun of a prophet's bald head!"
"Well" the father began, "It's like this. God was a really severe, angry guy in the old days. The creation had gotten all messed up, Lucifer had turned against him and even though he focused all his energy on a single group of people he couldn't get them to behave."
He took a breath, considering his next words and said, "Then around 4BC or so he saw this cute Jewish chick. He went down on, er, went down to Earth, got laid, had a kid out of wedlock and pretty much did a lot of the things he'd been grousing about for a few thousand years. It really mellowed him out."
The little boy looked up at his Father and said "Are you sure we're talking about God? That sounds an awful lot like the story Mom tells of how she met you."
The Father was shocked and asked "Why, what on Earth do you mean?"
"Well" said the little boy, "She was heading home from Synagogue, you were heading to the library for some of your Seminary studies-"
"Yes, well, your mother wasn't underage when we met. And I LEFT Seminary, God just went back to Heaven and left Mary to raise Jesus with her new husba-"
"Didn't they kick you out of Seminary for knocking up a Jewish girl?"
"I think it also had something to do with her being the Rabbi's daughter. Anyway, that's why we're Unitarians now."
The boy nodded sagely and asked, "So why am I circumcised then?"