coarse jesting: nimble, clever humor that slides into vulgar innuendo or flippant mockery
In everyday Greek this word named an admired social skill: the quick, well-turned wit of a cultured person, the knack for a clever remark that keeps a room entertained. Aristotle even ranked it a virtue, the happy middle between the clown who will do anything for a laugh and the stiff person who cannot take a joke. Its root idea is being "well-turning," nimble and versatile in speech.
Paul uses it only once, and he flips it. In his short list of things unfitting for God's people it stands beside "filthiness" (αἰσχρότης) and "foolish talk" (μωρολογία) as a habit of speech to leave behind, answered instead by thanksgiving. The very cleverness that made the word admirable is what makes it dangerous here: wit that turns coarse, suggestive, or shaming, using its verbal skill to make light of what should be taken seriously.
So the word carries a double edge a reader has to hold together: a real talent for humor, and that same talent gone wrong. Paul is not banning laughter or cheerful conversation. He is naming the point at which clever talk curdles into the vulgar or the merely frivolous, and calling the community to a different kind of speech.
Disputed
How broadly Paul's prohibition reaches: whether the word condemns only coarse, sexually suggestive humor, or witty, facetious speech more generally.
- majorityPaul condemns specifically coarse, obscene, or sexually suggestive humor, contextually narrowed by the surrounding sexual vocabulary (double entendre and innuendo, not humor in general).; BDAG, s.v. εὐτραπελία, 3rd ed., p. 414; P. W. van der Horst, 'Is Wittiness Unchristian? A Note on εὐτραπελία in Eph. v 4,' in Miscellanea Neotestamentica II (Brill, 1978), 163-177; Andrew T. Lincoln, Ephesians (WBC 42; Word, 1990), 322-324
- minorityPaul rejects the whole mode of facetious, witty speech and not only obscenity, aspiring to a community serious enough to tolerate no drollery at all.; Jeremy Hultin, The Ethics of Obscene Speech in Early Christianity and Its Environment (NovTSup 128; Brill, 2008), 190-210; R. C. Trench, Synonyms of the New Testament, §xxxiv
- minorityThe word is inherently ambivalent and only context condemns it; Paul rejects only degraded wit, leaving room for a genuine virtue of well-timed, moderate play.; Hugo Rahner, 'Eutrapelia: A Forgotten Virtue,' Geist und Leben 27 (1954): 346-353; Thomas Aquinas, Summa Theologiae IIa-IIae q. 168, aa. 2-4