Jake, Johnny, and Billy Bob went to the rodeo.  Unfortunately, a bull jumped the fence into the spectators and they were trampled to death.

Being good God-fearing men, they ascended to Heaven where they were met at the Pearly Gates by St. Peter. He said, "Welcome to Heaven, gentlemen. I'm sure you'll be quite comfortable here, but I must warn you that we do have our rules in Heaven. If you break them, you'll be punished. One rule is, never step on a duck. If you step on a duck, the duck quacks, then they all quack, and it just goes on and on."

That sounded simple enough. They passed through the Pearly Gates and were surprised to find there were ducks everywhere! In no time at all, Jake stepped on one. The duck quacked, then they all quacked, they made a terrible racket and it just went on and on. Pretty soon along came St. Peter with a terribly homely woman in tow. "I warned you that if you broke the duck rule you'd be punished." He chained the homely woman to Jake and said, "You will be together forever," and walked away.

Sometime later, despite his best efforts, Johnny accidentally stepped on a duck. The duck quacked, then they all quacked and made a terrible commotion that just went on and on. Sure enough, along came St. Peter with an even homelier woman. "I warned you that if you broke the duck rule you'd be punished." With that, he chained the woman to Johnny and said, "The two of you will be together for all eternity," and walked away.

Well, Billy Bob was very careful not to step on a duck.  One day St. Peter came along with a drop dead gorgeous blonde. He chained her to Billy Bob and said, "You will be together now and forever more," and walked away.

Billy Bob exclaimed, "Wow, I wonder what I did to deserve this?"

"I don't know about you," said the beautiful woman, "but I stepped on a duck..."