Menachem the Essene is a good example of this. As his Wikipedia page says:I don't think the line between the Pharisees and Essenes was ... what's the word I'm looking for ... solid?
Josephus says something similar about the Pharisees Pollio and Sameas (who are arguably Hillel and Shammai) in Ant. 14.9.4 and 15.1.1:Menahem the Essene (Hebrew: מנחם, Menahem) was a Jewish Tanna sage living during the era of the Zugot (lit. "pairs"). As such, he was "paired" with Hillel the Elder and served as Av Beit Din. The Mishnah, Tractate "Hagigah" 16b, states that he "went forth [out]", and as a result of that he was replaced by Shammai, who became from that point on the "Pair" mate of Hillel the Elder.
The Babylonian Talmud cites a dispute among the sages over where Menahem "went forth [out]" to. Abaye argues that "He went forth [out] into evil courses [culture]" (Hagigah, 16b), while Rava argues "He went forth [out] to the King's [God's] service" (Hagigah, 16b). The Gemara cites a quotation from one of the Baraitas supporting Rava's opinion: "Thus it is also taught: Menahem went forth [out] to the King's [God's] service, and there went forth [out] with him eighty pairs of disciples dressed in silk [regally]" (Hagigah, 16b).
The Jerusalem Talmud cites an additional opinion, that Menahem agreed to be appointed to a ministration position in order to revoke Governmental predestinations against Torah studying (Yer. Hagigah, 2:2).
The "Menahem" recorded in the Mishnah is thought to be the same as the one recounted in Josephus' (Antiquities of the Jews, b. 15, Ch. 10:5), in which a story is told about a 'Menahem' of the Essenes' sect. According to Josephus, when Menahem saw young Herod the Great going to school he clapped him on the back and addressed him as king, announcing to him that he would reign successfully, despite Herod not being in the line of the royal dynasty. When Herod became king, he asked Menahem how long his reign would be. Initially, Menahem didn't reply, and Herod urged him "Would my reign last ten years?". Menahem replied that Herod would reign at least 30 years, but did not specify the exact number. Herod was pleased with Menahem's answer and dismissed him with a clasp of the hand and thenceforth bestowed special honors upon the Essenes.
Nor did Sameas mistake in any part of this prediction; for when Herod had received the kingdom, he slew all the members of this Sanhedrim, and Hyrcanus himself also, excepting Sameas, for he had a great honor for him on account of his righteousness, and because, when the city was afterward besieged by Herod and Sosius, he persuaded the people to admit Herod into it; and told them that for their sins they would not be able to escape his hands.
So the Pharisees and Essenes had an arguable common origin in the Hasideans and some were later able to share a common political ground (whether pro-Herodian or pro-war), and Josephus says both groups had a similar view of immortality.And since Herod had now the government of all Judea put into his hands, he promoted such of the private men in the city as had been of his party, but never left off avenging and punishing every day those that had chosen to be of the party of his enemies. But Pollio the Pharisee, and Sameas, a disciple of his, were honored by him above all the rest; for when Jerusalem was besieged, they advised the citizens to receive Herod, for which advice they were well requited. But this Pollio, at the time when Herod was once upon his trial of life and death, foretold, in way of reproach, to Hyrcanus and the other judges, how this Herod, whom they suffered now to escape, would afterward inflict punishment on them all; which had its completion in time, while God fulfilled the words he had spoken.
For their [the Essenes'] 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 for ever; and that they come out of the most subtle 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
Ant. 18.1.3:They [the Pharisees] say that all souls are incorruptible, but that the souls of good men only are removed into other bodies, - but that the souls of bad men are subject to eternal punishment.
Ant. 18.1.5:They [the Pharisees] also believe that souls have an immortal rigor in them, and that under the earth there will be rewards or punishments, according as they have lived virtuously or viciously in this life; and the latter are to be detained in an everlasting prison, but that the former shall have power to revive and live again.
And since Josephus says that one of the founders of the Fourth Philosophy was a Pharisee (Ant. 18.1.1) and that, aside from their militancy, Fourth Philosophers "agree in all other things with the Pharisaic notions" (Ant. 18.1.6), it doesn't surprise me, given my view that the DSS are writings that were created by the other sects and older writings they brought them when they joined the Fourth Philosophy, that, as Davila discusses:They [the Essenes] teach the immortality of souls, and esteem that the rewards of righteousness are to be earnestly striven for.
... a great deal of technical terminology [is] shared between the Hekhalot texts [of Rabbinic Judaism] and the Qumran literature.
https://books.google.com/books?id=4UaaU ... ls&f=false