You've never been bullied, have you?
He isn't messing with him because he wants him to hit him back. He's messing with him because he thinks he won't hit him back. Bullies are cowards down deep, trust me. They lack self esteem and do things like this to prop themselves up. This guy won't get tired of messing with the OP as long as he thinks he'll never hit him back.
I was bullied from 3rd grade through 11th grade. Believe me, this is the voice of experience. I know bullies are cowards, and they're generally very unhappy people who would deserve help and sympathy if they weren't railing on people. But I have experienced that some of them are trying desperately to goad, to get a reaction. I put up with one for a few months in the way I'm suggesting the OP do, and the bully moved on.
Granted, they're not all the same...But fighting usually leads to more problems, unfortunately. When I read the OP's story, all those old feelings blossomed up and I just felt like taking the kid he's dealing with and beating him to a pulp. But like I say, it seldom solves anything.