The teachings of Jesus were powerful enough to amaze the crowds, silence the self-righteous, and convict the sinful. They were not, however, powerful enough to give birth to a spiritual family that would last thousands of years and could withstand the gates of hell. Only a resurrected Jesus could accomplish that. The church didn't make up the story of the resurrection to make Jesus look like a Savior. The church would not have existed to make up any stories if Jesus had never come out of his tomb.