Included in the message was the following etymology:

"Facetious" came to English from the Middle French word "facetieux," which  traces to the Latin word "facetia," meaning "jest." "Facetia" seems to have made  only one other lasting contribution to the English language: "facetiae," meaning  "witty or humorous writings or sayings." "Facetiae," which comes from the plural  of "facetia" and is pronounced fuh-SEE-shee-ee or fuh-SEE-shee-eye, is a far  less common word than "facetious," but it does show up occasionally. For  example, in a letter to the editor published in the Seattle Times,  August 26, 1995, a reader used the following words to describe a column written  by the humorist Dave Barry: "Hey, it's a HUMOR column, based entirely upon  facetiae."

If we are being facetious it should not be in the sense of the first definition:

Let no unwholesome word proceed from your mouth, but only such a word as is good for edification according to the need of the moment, so that it will give grace to those who hear. - Ephesians 4:29

We should also be kind in our speech so as not to fall into the trap spoken of in Proverbs 26:18-19:

Like a madman who throws Firebrands, arrows and death, So is the man who deceives his neighbor, And says, "Was I not joking?"

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