During his time on the island, Robinson Crusoe goes through a religious conversion. He was raised Puritan, but he commits sins such as rebelling against his father and failing to appreciate his class status. These decisions and feelings go against God. He suffers trials and misfortunes, ultimately winding up on an abandoned island, but his conversion is not complete until after he falls sick and nearly dies as a result of fever. He calls on God to deliver him and vows to serve Him afterward.
This story contains some parallels with the prodigal son parable in the Bible, in which the son leaves his father and squanders his fortune. When he returns, the father welcomes him with open arms.
Robinson Crusoe goes on to record reflections about his relationship to God, as well as his place in creation (which he had been dissatisfied with before). It is important to note that he also teaches Friday religion.