Faust's main problem was his temper. He lost his temper in the wrong place at the wrong time and was gagged for it. He tried on different accounts, but kept getting gagged. When he heard that the mod who had been gagging him was no longer a mod he tried again, but then he was IP banned.
To my knowledge, and this is just what I know so it's not necessarily a fact, the only rule he broke was to lose his temper and say some less then friendly things. At least it's the only rule involved with this, it is possible that he lost his temper prior to this event which would explain why he was perma-gagged then banned. It would be their way of preventing an unpleasant event from happening again.