What does Irving use to symbolize hypocrisy and hidden evil

Certainly Tom himself was hypocritical. Even after he finds out that his father had foolishly sold his soul to the Devil, Tom offers his own soul as well. After he has sold his soul, Tom pretends o be a religious zealot rebuking and criticizing people who are more pious than himself. Tom carries a big Bible around to seem like a true believer even though he has sold himself to the Devil. Tom also lends money for interest, a traditionally "un-Christian" practice, to vulnerable people.