Just Before I Die
Showing his friend around his his home, Jennings pointed out all of the collectibles he and his wife had acquired over their long years of marriage.
"The day before I die, I'd like to sell every piece we've got just to see how much it's all worth."
"Well," his friend replies, "since you couldn't possibly know the day before you were going to die, you'll never be able to sell!"
"And that's where you're wrong," the man smiled.
"If I sell it, my wife would kill me!"