I think you answered your own question. You know that only a flush is gonna make the call, so making a reraise is definitely a bad move. If hes bluffing and you reraise he is going to fold anway, so it doesn't make you any money. If he has the flush you lost atleast another 10 bucs. Fold or Call is the real question?? With almost 40 in the pot I would flat call and hope he is stealing.