Once upon a time the gods of old looked upon humanity, and were pleased with what they saw. They were pleased for among us they saw doctors, and teachers, and peacekeepers, a great step away from the animals armed with pointed sticks that we had previously been.
As a reward for how far we have come, and to aid us in our future improvements with miracles, the gods sent us one of their own, who took our form and origins so that we would not be frightened.
But in the age of science we did not believe in this god. We had grown to assume that all that occurred was mundane. His miracles were attributed to parlour tricks, natural phenomenon, and coincidences. At first we called him a liar, and we shunned him. Then we called him a manmad, and we tried to fix him.
Our attempts at repairs only broke him.
We broke him in such a way that he could not longer feel. His heart would no longer be filled with love, or blistered by sorrow, or blackened by hate. Only pain and pleasure motivated him.
This break was confined to his human form, but angered at our desire to not believe in them, and angered at what we had done to one of their own, the gods chose not to retrieve him from the flesh, but rather to let us suffer the consequences of what we had done.