[unglee]

Very strange. I assume you raised 4xbb in the CO with AJs because you wanted to take it down right there, right? Did you consider a fold when he minraised you preflop?

In any case, if the limp raiser has any of the "traditional" limp raising hands (AK, AA-QQ), he's not going to be especially scared by the flop. Even if he's a donkey limp raising something like 77-JJ/KQ-AQ, I think it'll be rather expensive to try to convince him he's beat on this non-threatening board. I think it's just too likely that he's trying to suck you in here. If you make a play at the pot and lose, you'll be left with an average or below average stack, so I'd probably let this one go and not invest any more since you have such a healthy stack.