But how do you seperate him from a look-alike?
I mean, logically, there's nothing stopping me or you or anyone else from putting on a robe, growing long hair and a beard, and then figuring out a magic trick way of parting or walking on water...
One step further, computers today and plastic surgery today, I bet if someone REALLY wanted to they could take a "picture" of Jesus as he's depicted in Christian imagery, use a 3-D computer to make the image a 3-D, real face, a representation fo what he would look like, and then have plastic srugery to have him look exactly like Jesus.
So- if he looks like a Savior, quacks like a Savior, walks on water like a savior, but he's really just a guy from Chicago who decided to pull a hoax...
How can you tell the "real" Jesus, if he arrived and said "Believe me! I'm back!" from that impersonator?