The story of Adam and Eve shows that humanity has a sinful nature and that we need God to help us live good lives. The books of the Old Testament also describe the rise of the Israelites, their covenant with God (an agreement for both sides to be faithful to one another), and their journey (called the Exodus) to the land promised to them by God.
The Israelites saw God in a different way than other early religions did. To them, God was seen as an all-powerful father who could be both angry and compassionate. God also cared enough about humanity to make direct contact with them. God often appeared to the Israelites in miraculous ways (creating everything from massive floods to a series of plagues) and was also said to have spoken to individuals on several occasions.
Both Christians and Jews believe in the idea of a messiah (“Anointed One” in Hebrew), a person sent by God to lead a group of people. The early Christians were those people (usually from Jewish backgrounds) who felt that Jesus Christ was the messiah and that his purpose was to bring humanity closer to God, to offer peace and assurance to humanity, and to promise eternal life after death for those who believed in God. The Jews who did not accept Jesus Christ as the messiah believed that the messiah would have a different purpose. They felt that the messiah would lead them to the land promised by God that they had lost after the Temple of Israel had been destroyed and they had been scattered to many different countries in 72 A.D. For them, Jesus Christ and his message of personal salvation just didn’t fit the role of the messiah that God was to send to them.
The Christians, on the other hand, not only accepted Christ as the messiah, but they had new beliefs that were not a part of the Jewish tradition. Christians felt that it was important that Christ be thought of as God incarnate (the idea that Jesus was God in a human form). Christians were also concerned about the condition of the human soul after death. In addition, Christianity was from the start a religion that wanted to convert all people.