Christians believe that death and suffering are due to sin, but not that either occurs in proportion to one's own sin. Rather, they believe that sin has corrupted the world, and that everyone--including cancer patients--is now living in that world.
In a world where sin has made suffering probable, the amount of suffering one experiences is simply a matter of probability. A roll of the dice.
I see. So Yahweh gives NO additional protection to any of his followers on earth. You get good times or you get bad times simply at random - god sends no favours, sends no smites, gives no protection from the bad stuff that happens. That's a rather bleak religion to follow, I'm not sure where the appeal lies in a "good" god who doesn't lend any assistance to his devoted followers?
It's interesting that you bring up Job, because Job is actually a response to that theology, using a story to refute it as an adequate explanation for human suffering given the observation that exceptions to that system definitely seem to occur. Job's friends are stand-ins for that older way of thinking, and by the end of the story God Himself comes down to refute their claims.
Interesting YOU bring up Job, because it seems to give the opposite view to the two paragaphs I've quoted above - that Yahweh DOES provide protection from the bad (else why else would Satan say "Hast not thou made an hedge about him, and about his house, and about all that he hath on every side?") because he has to remove
that protection for Satan to be able to touch Yahweh's follower. And, of course, once the little wager was over, Yahweh "blessed the latter end of Job more than his beginning: for he had fourteen thousand sheep, and six thousand camels, and a thousand yoke of oxen, and a thousand she asses". Sounds like we SHOULD expect good things to come to those who believe, and bad things to happen to those Yahweh turns away from.
So I'm a little confused here Mooby - do we reap in this world what we sow, or not?