“Didymon the flute-player, on being convicted of adultery, was hanged by his namesake.” This ancient Greek joke is quoted as an example of a chreia in Aelius Theon's Progymnasmata. It makes use of at least two correspondences. On one hand, two different meanings of the word δíδυμ are involved. First, it is the flute player's name, meaning “twin brother” (as with Jesus' disciple “Thomas called Didymus”); the second half of the joke evokes the plural of the word in the meaning of “testicles.” On the other hand, the flute player's punishment corresponds to the sin that he committed. Beyond these primary and obvious sources of humor, the anecdote implies several other levels of meaning. For example, it can be interpreted in the framework of widespread associations of flute players with gaiety: “[aulos] was an instrument that produced bawdy music and deformed the face and so was not proper for free women, or even citizen men. Plato (Republic I.399d) banned it from his ideal city, and according to Aristotle (Politics 1341), citizens could listen to it, but should not learn to play it for it was not considered a ‘moral’ instrument.” Our text adds an unexpected twist to the popular image of flute players: whereas in most literary references they appear as instruments or objects of ecstasy and lust, the Didymon joke characterizes its protagonist as the originator of sexual transgression. Thus the text confirms as well as generates prejudice.