In the story "the devil and tom walker" why is it important that tom has no bible with him when he answer the three knocks on his door?

The Devil take me," said he, "if I have made a farthing!"

This statement illustrates irony of situation. For, Tom Walker in his miserly way is simply mitigating his financial gain from the man, but the reality is that the Devil does actually take him. Three knocks come at Tom's door; there stands a black man with a black horse, who tells Tom that he is "come for." Because Tom has left his big Bible on the desk and the little one in his coat, Tom is "taken."