" It is not even accurate to say that Christianity eventually broke away from Judaism. It is more accurate to say that, out of that matrix of biblical Judaism and that maelstrom of late Second-Temple Judaism, two great traditions eventually emerged: early Christianity and rabbinic Judaism. Each claimed exclusive continuity with the past, but in truth each was as great a leap and as valid a development from that common ancestry as was the other. They are not child and parent; they are two children of the same mother. So, of course, were Cain and Abel. "

― John Dominic Crossan , The Birth of Christianity