If Jesus existed, he was most likely just a slightly deluded con-artist/preacher/cult leader, who over-reached himself, became inconvenient for the authorities and paid with his life. I don't think he meant to die any more than the protagonist of "The Life Of Brian" did. And just like Brian, he'd probably be pretty miffed to hear his supposed friends and followers calling his crucifixion a voluntary one.
"The fact that a believer is happier than a skeptic is no more to the point than the fact that a drunken man is happier than a sober one." - George Bernard Shaw