John the Baptist and Banus are real historic people.
John
http://www.josephus.org/JohnTBaptist.htm
Life 2
When I was about sixteen years old I had a mind to make a trial of the several sects that were among us. There are three of these, that of the Pharisees, the Sadducees, and the third that of the Essenes, as we have frequently told you. I thought that being acquainted with them all I could choose the best.
So I consigned myself to hardship, and underwent great difficulties, and went through them all. Nor did I content myself with the trying of these three only, for when I was informed that one whose name was Banus lived in the desert, and used no other clothing than what grew upon trees, and had no other food than what grew of its own accord, and bathed himself in cold water frequently, both night and day, to purify himself, I imitated him in those things, and continued with him three years.
Comment
The Popularity of John the Baptist
Both the New Testament and Josephus depict John the Baptist has having a more powerful influence on the majority of the people of the time than did Jesus. Josephus’ description of John is more detailed than his account of Jesus, and John’s death is, in the people’s view, avenged afterward by Heaven with real actions, but Josephus mentions no such divine support for Jesus. In contrast with his usual attitude toward popular leaders, Josephus is sympathetic towards John the Baptist. One wonders what the difference is between John and the men whom Josephus disparages as “deceivers” (apateônes) and “enchanters” (goêtes), such as Theudas and the Egyptian. It isn’t simply that John did not represent a direct threat to Rome — Josephus always stresses the folly of those who do oppose Rome — as many of the others also seemed apolitical. All of these, including John, seemed to be killed solely because they had a large following, which in itself was seen as a threat to those in power: there was room for only one crowd and only one leader. We are left to conclude that Josephus himself was touched favorably by the philosophy of John, just as many of his countrymen were. While he was probably working from a source that was itself positive toward John, his choice of that source would have reflected his own attitude.
A Baptism of Repentance
Josephus seems genuinely intrigued by the notion of baptism and tries to explain it in terms his audience can understand. (The word derives from the Greek baptô, “dip”.) He understands it first as a purification of the body, playing the same role as the traditional mikvah. The spiritual question involved is whether John has the power to forgive sins, perhaps with the aid of water that has mystical properties. Josephus strongly denies that John claimed any such power: the washing was a physical manifestation of a spiritual commitment to performing good works. In the New Testament John gives a “baptism of repentance,” and insists angrily to those who come to him that they must “bear fruits worthy of repentance,” an attitude which accords with Josephus’ description. But he is also seen as providing “forgiveness of sins” after the repentance has been made, and the religious authorities, particularly in the Book of John, are suspicious that he is taking upon himself a divine role. His follower Jesus is more directly accused of this in the other Gospels.
Josephus does not hint that John was announcing the imminent coming of the Messiah, as the New Testament does. But throughout his works Josephus deliberately hides references to the Messiah (for example, in his account of Moses he leaves out Deuteronomy 18) — except to describe the notion as a primary cause of the war with Rome, which was evidently well known to his non-Jewish audience (the Roman historian Tacitus also mentions it), which is reason enough for him to not want to provoke his audience by presenting the idea positively. Yet it is difficult to understand the excitement of the people in response to John simply based on the description of his philosophy as given by Josephus.
Essenes
Modern scholars see a similarity between John and the sect that wrote the Dead Sea Scrolls, who are usually taken to be the Essenes described by Josephus. John may have once been an Essene who developed a following of his own. This may explain Josephus’ favorable view of John, for the Essenes are described in very much greater detail than the other two major Jewish philosophies. Moreover, in his autobiography, Josephus tells us that when he was a teenager he spent three years in the desert with a man named Banus who resembles John in behavior (as in Mark’s description). This Banus clothed himself using only trees, ate only food that was found in the wild, and bathed himself in cold water several times a day. Yet this Banus was not an Essene, but a unique individual. This experience seems to have given Josephus a lasting sympathy for people who led this way of life, which is quite probably why he speaks so favorably of John the Baptist.
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