Tom turned to the church in order to trick the Devil and get out of his bargain.  Tom worried about his after ife and began to see his evil ways, but it still didn't stop him from using his old ways in bankrupting people and trying to "cheat" the Devil. Again, church was just a means to an end for him and he put on a good show by pretending to read the Bible to try to save his soul.  He kept the small Bible in his pocket and the large Bible on his countingdesk. He was always reading the Bible whenever anyone would come in for services.  His last task on Earth was to ruin a man whom he had a good friendship with and the man asked him for a few more days.  When Tom said no to the man he said that he had made a lot of money off him. Tom said, The Devil take me," said he, "if I have made a farthing!"  The Bible he professed to read had not taught him anything about love, compassion, sin, and truthfulness.  The Devil showed up on the spot and carried him away to his new home where sinners end up.

Tom turns to the Church because he is worried about his deal with the devil. As he grows older, the idea of his mortality becomes closer to his thoughts, and he most likely is thinking about the afterlife. In an attempt to thwart the devil from taking his soul, Tom carries the bible and goes to church. The plan clearly didn't work, as the devil came, and his late-in-life devoutness didn't amount to anything.