Another possible theistic perspective: atheism in and of itself isn't a "sin" unless the atheist goes the extra step and denies whichever god(s) the religion in question cares about.The point is that us an atheist's perspective, but there is a flip side. From an atheist's point of view Bob is purely an atheist in his ignorance, but on the Thirst's point of view his ignorance will b pardoned, because it isn't a sin to not know.