Here's a long story that is similar to the situation, I was told this was how Jack O'lanterns were inspired.

There was a horrible man in Ireland that did nearly every terrible thing under the sun, he drank too much, fight everyone and stole things. One day the devil made a personal visit to take his soul down to hell, well Jack was quick with the tongue and manage to trick the devil into becoming a shilling for one last pint.

Thing was Jack had a cross on that wallet, he manage to trap the devil in there until the devil made an agreement to let Jack live another year on earth, but only if Jack repent his ways and became a better man. Jack agreed, and the devil was released only to return to hell empty handed.

The year pass, Jack did not repent, in fact he became worse and the devil showed up for the deal. Again Jack's silver tongue convinced the devil for a favor, an apple from the tallest tree.

As the devil climbed Jack had carved a cross into the tree, telling the devil he is willing to to make a deal for ten years on earth. The devil had no choice, agreeing Jack but only if Jack repent, after agree he removed the cross as the devil gone to hell empty handed again.

Years pass, Jack became possibly the worse man in Ireland at the time, and soon the devil came for his soul. Jack tried his tricks, only this time it wouldn't work, because even God had became fed up with this man's antics and allowed the devil one free pass.

Dragged into the darkest part of hell, Jack begged and plead about how he will change for real this time, and the devil did feel sorry for him. He tossed him a piece of coal, which Jack had placed in the only idea he had left, a turnip which he had hollowed out right there, to carry that coal through the darkness.

The moral is some times no matter how much somebody say they will repent, they won't, and they will become much worse each time.