The differing beliefs that emerged between Christianity and Judaism, especially in the first two centuries AD, were mainly caused by the introduction of heavenly beings in the Jewish religion. This resulted in the predominance of a messiah, who will be sent by God as salvator mundi. Mainly Paul preached and practiced the conversion of pagans to Christianity, without obligating them to practice the Jewish law. In the course of time the baptized pagans represented the mainstream of Christianity which caused a conflict between them and those Jews who practiced the Jewish law but also believed in Jesus as the Messiah. The development of these tendencies is described in this book.