Raise preflop to isolate the limper, your hand is probably better than the avg of his range of hands, and you have position. Plus, you want the blinds to fold to get dead money in the pot.

If you had raised preflop, you'd have defined your hand more, which would make the flop fold reasonable. Since you limped in, he won't give you credit for a good ace, and would 3bet with a wider range of hands, making a calldown correct.