The Pope died and went to heaven, (of course). There, he decided to study the history of religion and spent many eons going back over the scriptures passed down from the beginning of time.
One day, there was a loud agonized scream from the library where the Pope was studying and Saint Peter rushed in to ask what was the matter. The Pope sobbing hysterically said, "the R is missing... they left the R out!"
Saint Peter, feeling perplexed, asked, "what do you mean? What about the R?"
The Pope, with tears running down his face, his face twisted in agony, sobbed, "the word is CELEBRATE!"