The Asclepius survives complete only in a Latin translation, the Greek having been lost apart from fragments, and a Coptic version of part of it turned up at Nag Hammadi. It is a dialogue in which Hermes instructs Asclepius, and it is the most theologically ambitious of the Hermetic writings.
It is remembered for two passages. The first is the god-making passage, which describes how the ancestors learned to draw divine presence down into statues by means of herbs, stones and scents, so that the images became animate and could speak and foretell. Nothing else in surviving pagan literature states the theurgic rationale for cult images so directly, and it is why the Asclepius was both prized and feared in the Renaissance. Ficino handled the topic with visible caution, and Giordano Bruno did not.
The second is the Lament, a prophecy that Egypt will be abandoned by its gods, its temples filled with corpses, and its sacred learning disbelieved. Augustine quotes it at length in the City of God in order to attack it, and that hostile quotation is part of why the text stayed in circulation through the Latin Middle Ages when most of the Hermetica did not.
The Coptic fragment recovered at Nag Hammadi covers part of the same dialogue and differs from the Latin in places, which gives scholars a rare second witness to a Hermetic text and shows the Latin translator smoothing where his source was awkward.