Human pain cannot compare to jesus christ's. So it is spread out evenly through each individual's life span?

Setting aside the fact that this character did not exist, and the logical inconsistency of notions like "died for your sins", your own holy book's stories call bullshit on you here. According to the Bible, Jesus was crucified right beside two other guys. Those two guys likely suffered similar pain. Also, crucifixion, while an unpleasant death, is certainly not the most unpleasant imaginable, in part because it only takes a matter of days to die, and some people spent years being tortured first (see, for example, the holocaust). Crucifixion was not even the worst way the Romans knew of how to kill people. You suffer from a lack of imagination if you think crucifixion is the worst imaginable death.