Rabbi Abraham Heschel on fundamental differences between Judaism and Christianity

Christianity starts with one idea about man; Judaism with another. The idea that Judaism starts with is that man is created in the likeness of G-d. You do not have to go far, according to Judaism, to discover that it is possible to bring forth the divine within you and the divine in other men. There is always the opportunity to do a mitzvah. It is with that opportunity that I began as a Jew. Christianity begins with the basic assumption that man is essentially depraved and sinful – that left to himself he can do nothing. He has to be saved. He is involved in evil. This is not the Jewish way of thinking. The first question of Christianity is: ‘What do you do for the salvation of your soul?’ I have never thought of salvation. It is not a Jewish problem. My problem is what mitzvah can I do next. Am I going to say a blessing? Am I going to be kind to another person? Am I going to study Torah? How am I going to Honor the Sabbath? These are my problems. The central issue in Judaism is the mitzvah, the sacred act. And it is the greatness of man that he can do a mitzvah. How great we are that we can fulfill the will of G-d! But Christianity starts with the idea that man is never able to fulfill the will of G-d. All he has to do, essentially, is to wait for salvation. (Rabbi Abraham Joshua Heschel, quoted in What Christians Should Know About Jews and Judaism. World Books, Rabbi Yechiel Eckstein, Chapter 2, page 66).

If you declare with your mouth, “Jesus is Lord,” and believe in your heart that God raised him from the dead, you will be saved. For it is with your heart that you believe and are justified, and it is with your mouth that you profess your faith and are saved. (Apostle Paul, Romans 10:9-10)