Well worth a few minutes of your time:
Jesus Existed writes Craig S. Keener
Contrary to some circles on the Internet, very few scholars doubt that Jesus existed, preached and led a movement. Scholars’ confidence has nothing to do with theology but much to do with historiographic common sense. What movement would make up a recent leader, executed by a Roman governor for treason, and then declare, “We’re his followers”? If they wanted to commit suicide, there were simpler ways to do it.
. . . Logically, why would Jesus’ followers make up a Jesus to live and die for? Why not glorify real founders (as movements normally did)? Why make up a leader and have him executed on a Roman cross? To follow one executed for treason was itself treason. To follow a crucified leader was to court persecution. Some people do give their lives for their beliefs, but for beliefs, not normally for what they know to be fabricated. Jesus’ first movement would not have made up his execution or his existence.