According to most Christian interpretations of the Bible, the theme of Jesus' teachings was that of repentance, unconditional love,[Jn. 13:34–35] forgiveness of sin, grace, and the coming of the Kingdom of God. Starting as a small Jewish sect, it developed into a religion clearly distinct from Judaism several decades after Jesus death. Christianity spread throughout the Roman Empire under a version known as Nicene Christianity and became the state religion under Theodosius I. Over the centuries, it spread to most of Europe, and around the world.
Concept of God:
Jesus presented a view of God as more lovingly parental, merciful, and more forgiving, and the growth of a belief in a blissful afterlife and in the resurrection of the dead. His teachings promoted the value of those who had commonly been regarded as inferior: women, the poor, ethnic outsiders, children, prostitutes, the sick, prisoners, etc. For over a thousand years, countless hospitals, orphanages, and schools have been founded explicitly in Jesus' name. Thomas Jefferson considered Jesus' teachings to be "the most sublime and benevolent code of morals which has ever been offered to man".
Concept of salvation:
Jesus and his message of salvation have been interpreted, explained and understood by many people. Paul of Tarsus, in his influential epistles which were the earliest writings of the New Testament, espoused that salvation was based on Jesus alone, acknowledging the positive value of the Jewish Law but considering it unnecessary to salvation.The Church Fathers of the early centuries further defined Jesus' identity as fully God.Ancient and medieval thinkers, such as Augustine of Hippo, further defined Jesus' divine and human natures.Enlightenment and Reformation theologians concerned themselves less with defining Jesus' identity as with understanding his work in redemption.
Not all have agreed. In the 1800s, German scholars questioned Jesus' miracles and some, such as David Strauss, portrayed him as merely a man, hence incapable of providing one's eternal salvation.C. S. Lewis and Pope John Paul II have defended the Jesus of faith against historical critics.