The Perates or Peratae (Περατής, "to pass through"; πέρας, "to penetrate") were a Gnostic sect from the 2nd century AD. The Philosophumena of Hippolytus is our only real source of information on their origin and beliefs. The founders of the school were a certain Euphrates (whom Origen calls the founder of those Ophites to whom Celsus referred about 175 AD) and Celbes, elsewhere called Acembes and Ademes.
It had been known from Clement of Alexandria that there was a sect of that name, though he tells nothing as to its tenets. Hippolytus was acquainted with more books of the sect than one. One called Oi Proasteioi appears to have been of an astrological character, treating of the influence of the stars upon the human race, and connecting various mythologies with the planetary powers. There was besides a treatise which resembles the doctrine of the Naassenes.
The title "Peratic," as applied to the sect, is explained by Clement of Alexandria as one derived from place. In this sense it may have taken its origin from the phrase Ἅβραμ ὁ περατής (, LXX), which was understood to mean one who came from the other side of the Euphrates. Pliny, speaking of a certain gum which came from Arabia, India, Media, and Babylon, adds that that which came from Media was called by some Peratic. This seems to be the same as the Peratic frankincense spoken of by Arrian. It is probably a mere corruption that Sophronius of Jerusalem speaks of Euphrates "Persicus," for he clearly got the name from Theodoret; yet the corruption may have originated in the change of an unfamiliar word into a supposed equivalent. On the whole, we may conclude that this Euphrates, if he existed, came from the extreme east.
Bunsen has suggested that this designation can mean Euboean. He founds this conjecture on the facts that Acembes, with whom Euphrates is coupled, came from Euboea, and that Euboea is sometimes spoken of as ἡ πέραν, the other side.