I think the evidence for it is very slim, but Josephus’ Essenes might be a catchall for Gnostics. Though how Josephus describes the Essenes in more detail they seem to be more like a sect full of “Daniels” – Jewish prophets for Gentile kings. Simon the Essene (AJ 17.13.3), for example, seems to follow the same pattern of Daniel and Nebuchadnezzar’s dream. Josephus says that the Essenes “live the same kind of life as do those whom the Greeks call Pythagoreans” (AJ 15.11.4)
By the time Josephus had been writing, however, Neo Pythagoreanism was flourishing. This is probably just a modern way of separating the doctrines of Pythagoreans from later (Neo) Pythagoreans contemporary to Josephus. This is from Wikipedia:
Neopythagoreanism was a revival in the 2nd century BC—2nd century AD period, of various ideas traditionally associated with the followers of Pythagoras, the Pythagoreans. Notable Neopythagoreans include first century Apollonius of Tyana and Moderatus of Gades. Middle and Neo-Platonists such as Numenius and Plotinus also showed some Neopythagorean influence.
They emphasized the distinction between the soul and the body. God must be worshipped spiritually by prayer and the will to be good. The soul must be freed from its material surroundings by an ascetic habit of life. Bodily pleasures and all sensuous impulses must be abandoned as detrimental to the spiritual purity of the soul. God is the principle of good; Matter the groundwork of Evil. The non-material universe was regarded as the sphere of mind or spirit.
Does Josephus mean that their philosophy was the same, or their mystical practices were the same? Josephus makes the same claim about the Pharisees (their way of living is like the Stoics from Josephus’ autobiography). Obviously, the Pharisees and Stoics don’t share the same belief systems, but quite possibly their overall philosophy is the same. In this respect, maybe Josephus is saying that the Essenes’ overall philosophy of asceticism is similar to the Pythagoreans.
The thing is, though, that Neopythagoreans had a lot of influence on 2nd century Gnostics. And Essenes seem to disappear right around the time that Gnostics start emerging. If anything, it should have been the Gnostics that lived like Neopythagoreans, not Essenes.
Some other things that Josephus writes about Essenes:
- Most don’t marry, but some do (JW 2.8.12)
- They seem to have wandering preachers. But if not preachers, they take in those of their kind in different cities, which seems to mirror the Didache (JW 2.8.4)
- JW 2.8.11: “For their doctrine is this: That bodies are corruptible, and that the matter they are made of is not permanent; but that the souls are immortal, and continue forever; and that they come out of the most subtile air, and are united to their bodies as to prisons, into which they are drawn by a certain natural enticement; but that when they are set free from the bonds of the flesh, they then, as released from a long bondage, rejoice and mount upward”
So, who knows. There are a lot of things contrary to what we know about Gnostics that the Essenes seem to practice, but what we know of both groups is obscured by what’s lost in history.