Some of Tom Sawyer's negative traits are his mischievousness, ability to manipulate others, and his selfishness. For example, in the famous whitewashing scene, Tom manipulates the other boys into doing his punishment of white washing the fence for him by making painting the fence seem like a difficult job that not many people can do. Because Tom presents the task in that way, the boys are eager to jump at the chance to show they can paint the fence too, giving Tom "treasures" in exchange for a chance. Tom manipulates his friends for his own benefit. He gets out of his punishment and receives items in return.
Those treasures Tom uses to exchange for tickets from Sunday School, tickets earned for memorizing Bible verses. Tom's lack of knowledge of the Bible is apparent, when after proudly showing his unearned tickets and receiving his Bible, he declares two of the disciples to be David and Goliath. Tom does not want the Bible so he can go home and read it; he selfishly wants recognition for accomplishments not his own.
The last example of Tom's selfishness is when he, Joe, and Huck run away to Jackson's Island to become pirates. Tom is feeling low and wants to escape. However, he does not care about the repercussions of his leaving. Everyone back in town thinks the boys are dead. Joe's mother and Aunt Polly are distraught. Tom sneaks away from the island to secretly visit Aunt Polly to see if people are devastated over his absence. He wants to know if people are missing him.