How is Mr. Bumble presented as both a comic and tragic figure?

Mr. Bumble is the beadle of the parish, a fat and choleric man who takes great joy in abusing those below him. As his name suggests, Mr. Bumble isn't very smart and is rathar bumbling. He is quick to give up Oliver if there is money involved. Mr. Bumble sees a wanted advertisement for Oliver in London. Bumble hurries over and tells the men everything he knows of Oliver, and Mr. Brownlow pays him.