He tried to make Jesus Aryan. Hitler had a long history of conflict with the Catholic Church, and with mainstream Christianity in general, and this was only amplified by his appointment of Alfred Rosenberg, a neo-pagan, as the head ideologist of the Nazi Party. Both Hitler and Alfred attempted to re-educate the Protestant populations of Germany with the unified Protestant Reich Church, and the Deutsche Christen movement. The Deutsche Christen movement began teaching people throughout Nazi German the idea that Jesus was an Aryan, and Saint Paul was a Jew. It claims that Saint Paul had lied about the origins and message of Jesus in order to gain power for the Jews. They attempted to compile a "People's Testament", or Fifth Gospel in order to eliminate "Jewish influences on the Bible". This movement was met with little success, and lost momentum while Hitler too lost interest with it.

In short, he tried to convince people that Jesus wasn't really Jewish, but it wasn't as effective as he would have hoped.

Sources: Susannah Heschel, The Aryan Jesus: Christian Theologians and the Bible in Nazi Germany, Princeton University Press, 2008.

Cecil, Robert, The Myth of the Master Race: Alfred Rosenberg and Nazi Ideology, 1972.

Steigmann-Gall, Richard, The Holy Reich: Nazi Conceptions of Christianity. Cambridge: Cambridge University Press, 2003.