In Washington Irving's short story The Devil and Tom Walker, the protagonist, Tom, does not immediately accept the devil's offer to place Kidd's treasure within Tom's reach. The circumstances by which the treasure came to be within Tom's reach was based upon the fact that the devil had "conceived an especial kindness for" him.
As for the reasoning by which Tom did not immediately accept the treasure from the devil, this is never "disclosed publicly"--for either the reader or the characters (narrator/society) in the story. What this means is that readers never find out what took Tom so long to accept the offer of the treasure by the devil.
Readers can assume though, through the narration, that the terms must have needed to be considered with special care given that Tom "was not a man to stick at trifles where money was in view."
The excerpt from which the answer's quotes were derived from are found in the following passage from the story:
These he offered to place within Tom Walker's reach, having conceived an especial kindness for him: but they were to be had only on certain conditions. What these conditions were, may easily be surmised, though Tom never disclosed them publicly. They must have been very hard, for he required time to think of them, and he was not a man to stick at trifles where money was in view.