Don't feed the aikiweb troll...
Anyway, to the original post... Comments of that nature are totally inappropriate. Really there is no wiggle room there. Obviously not being there none of us can say too much, but if the original post is even remotely accurate then I would join the chorus and say it is time to leave. Give your reasons if you can, but.. in the end staying and not saying anything is (at least to some extent) implicitly supporting the behavior. And I certainly wouldn't recommend recruiting new students for the fella...
Walk away. Tell him why if you can. What you need to do may be difficult for you to do, but I don't find the situation itself particularly difficult to understand. So there isn't much more to say and the ball is really in your court...
My .02. And worth every penny of that...