Earlier quoted context omitted.
He's quite racist[0] and people won't tolerate his hate. It's for the best he got hellbanned, so the "saner" ones won't be tempted to get into a flame war with him. [0]: http://i.imgur.com/IIMGYKE.png (the last comment made me laugh)
He's not necessarily racist. He's suffering from a mental illness. He believes god talks to him.
It does mean we should judge him less for it. But it also means it might be a good decision to ban him so that he does not tarnish the community with too many flame threads.