1. We know that there was a range of different views in Second Temple Judaism as related by Josephus and we find a similar variety in the NT. Paul seems closest to OT views of divine judgment of the wicked in a moment of destruction (annihilation), while Revelation and Matthew seem closest to ideas of eternal torment in Judaism; see David Sim’s Apocalyptic Eschatology in the Gospel of Matthew (Cambridge, 1996) for a full discussion of such views in Matthew. For similar views in early Judaism, see 1 Enoch 5:5, 22:11, 100:3, 1QS 2:8, 4:11-14, Judith 16:17, Testament of Judah 25:3-5, 4 Maccabees 9:7-9, 12:11-12, Josephus, Bellum Judaicum 2.165, 2 Baruch 44:12-15. These pair terminology of eternity with suffering and/or punishment. One may quibble on whether eternity is hyperbolic and not truly unbounded but rather includes a consummation, but there was a clear concept in Second Temple Judaism of perpetual eschatological suffering, a concept that existed alongside the older OT notion of annihilation as divine retribution.
2. Is Playo’s myth of Er the root of the Jewish/Christian idea of postmorterm punishment? There are three main avenues through which the idea developed (that Ehrman highlighted in his book “Heaven and Hell”).
3. (1) First is the Greek concept of Tartarus borrowed in the myth of the Watchers in the Book of Watchers in 1 Enoch. The Watcher myth, particularly the character of Asael, is based on Hesiod and the myth of the Titans, Prometheus in particular. See George Nickelsburg’s Hermeneia commentary for a fuller discussion. The fallen angels are thrown into an abyss deep under the earth where they are punished with fire in dense darkness. This is based on the myth of Tartarus which is named in some copies of 1 Enoch. (Note that 2 Peter 2:4 refers to Tartarus and its parallel in Jude 6 likewise borrows from Hesiod’s description of Tartarus) What then happened in Enochic Judaism is that punishment in the fiery abyss that was originally reserved for the fallen angels was then extended to the wicked who are judged by God. We can find this process in the gospel of Matthew itself, which not only says that the wicked share the same fate as the demons but it even borrows language from 1 Enoch (10:4 = Matthew 22:13, a near verbatim quotation) that originally referred to the punishment of the Watchers but applied it to evildoers facing eternal punishment.
4. (2) The second potential source is Zoroastrian eschatology which first concerns an individual judgment of the soul at death and a final judgment of the resurrected person at the end of the present world. The first involves a descent (via a narrow bridge that leads to either torments or paradise) into an underworld of torments and an ordeal by molten metal (which is purifying and thus of limited duration) and the latter involving a final destruction of evildoers with molten metal. The concept of Judgment Day found in Enochic sources as well as in the NT bears striking similarities with Zoroastrian ideas and the Kinvat bridge itself is possibly attested in a Qumran text. For further discussion on the latter, see Vincente Dobroruka’s Persian Influence on Daniel and Jewish Apocalyptic Literature (Bloomsbury, 2022).
5. (3) The third major trajectory is the development of the concept of Gehenna, which was exegetical of Isaiah 66:24 (cf. Mark 9:43-49). This text described the unending burning of corpses in sight of worshipers at the Jerusalem temple (i.e. burning in the Hinnom valley, which draws on earlier conceptualization of this location as a Tophet), which in later Second Temple times became applied to souls of the dead, then the wicked who awaken in the resurrection, and even those who suffer in fire forever (1 Enoch 26-27, Daniel 12:2, Judith 16:17). This was an influential text because it depicted the destruction of the enemies of God as an enduring and lasting situation, rather than a one-time event, and the later reinterpretation applied to sinners the kind of punishments experienced by the fallen angels. Matthew draws on this eschatology and uses language that presumes an enduring situation of post-judgment punishment in a place of detention with everlasting punishment resulting in suffering (again see Sim’s book for a full analysis).
6. Ehrman thinks Jesus’ images of judgement refer to destruction, not torture. He thinks eternal punishment isn’t punishment that goes on forever, but that its result — being dead — is permanent. He cites 1 Enoch, but thinks it’s imagery means the same thing.

Dr. Glenn Peoples has a good video on early church fathers who reflected an annihilationist viewpoint: https://youtu.be/je3AW6QeXzk

Same with Heiser: https://podcasts.google.com/feed/aHR0cHM6Ly9uYWtlZGJpYmxlcG9kY2FzdC5jb20vZmVlZC9wb2RjYXN0/episode/aHR0cHM6Ly9uYWtlZGJpYmxlcG9kY2FzdC5jb20vP3Bvc3RfdHlwZT1wb2RjYXN0JnA9MzM4Mw?ep=14

Part 2: https://podcasts.google.com/feed/aHR0cHM6Ly9uYWtlZGJpYmxlcG9kY2FzdC5jb20vZmVlZC9wb2RjYXN0/episode/aHR0cHM6Ly9uYWtlZGJpYmxlcG9kY2FzdC5jb20vP3Bvc3RfdHlwZT1wb2RjYXN0JnA9MzM4NA?ep=14

1. Judaism: The Evolution of a Faith:
2. The belief in the afterlife develops more broadly in apocalyptic literature. It is clearly from these sources, that the complex of afterlife beliefs in Rabbinic Judaism should be traced. The oldest biblical faith certainly included a concept of life after death, in which in some indescribable manner the human continues a shadowy form of existence in a place called Sheol, the Pit, or Abaddon, deep beneath either the earth or the cosmic ocean. But individuals sought more than this vague afterlife. They yearned for fellowship with God and vindication for undeserved suffering in this world. The belief in a shadowy existence was only a small step from an affirmation of a spiritual existence that follows death, and consequently of a doctrine of nonphysical immortality. Such gropings for immortality and also resurrection begin to surface at Job 14:13-15; Isaiah 26:29; and Daniel 12:2. With these stirrings of faith in an immortal life of bliss for the righteous arise the notions of heaven and hell. These notions are nurtured in apocalyptic literature in a manner hitherto unknown in biblical works. It is not always clear whether the punishment of the soul takes place after death or after final judgment. Nor is it always certain whether Gehenna, where punishment ensues, is subterrestrial; or whether Gan Eden (Garden of Eden, Paradise), where reward is received, is in heaven. These ambiguities were never settled and continued on into rabbinic literature and throughout the history of Judaism. Similarly, it is difficult to ascertain whether resurrection is to take place on this earth, or on a recreated earth; whether it precedes the age to come, or is to constitute that age; whether it is heavenly and spiritual, or part of a real this-worldly messianic kingdom; whether it is only for the righteous (Dan. 12:2), or for all human beings (Test. Benj. 10:8).
3. The Anchor Yale Bible Dictionary:
4. A doctrine which teaches that the souls of humans and even animals had a prior existence before being born into mortal bodies. In its appearance among Jewish and early Christian writings, this teaching commonly exhibited influences from Platonic thought. But it also has biblical ties. A notable example consists of these words of the Lord to Jeremiah: “Before I formed you in the womb I knew you, and before you were born I consecrated you; I appointed you a prophet to the nations” (Jer 1:5). A second excerpt which recalls this notion is found in the series of questions put to Job by the Lord about the formation of the earth: “On what were its bases sunk, or who laid its cornerstone, when the morning stars sang together, and all the sons of God shouted for joy?” (Job 38:6–7). Antecedent influences on this excerpt are difficult to trace, although the Psalms speak of celestial hosts who sing praises to the King of Heaven, echoing Ugaritic poetry (cf. Pss. 19:2; 29:2; 148:2–3). It is conceivable that this concept formed an aspect of Paul‘s belief, its origins likely lying in his Jewish background. Referring to his turning away from persecuting followers of Jesus, Paul speaks of God as “he who had set me apart before I was born” (Gal 1:15). Another passage, which consists of a thanksgiving to God, reads as follows: “even as he [God] chose us in him before the foundation of the world” (Eph 1:4). Aside from the issue of the Greek vocabulary used here, the verse seems to affirm that in the beginning a celestial plan had been formulated to select persons to fulfill God‘s purposes; a second dimension may be that God‘s selection was carried out among persons during a preexistent state.
5. Jewish sources also reveal the idea of a preexistence. The Wisdom of Solomon, dating to the 1st century B.C.E. and exhibiting Platonic influence, has Solomon say the following in a prayer: “As a child I was by nature well endowed, and a good soul fell to my lot; or rather, being good, I entered an undefiled body” (8:19–20). 2 Enoch, whose origin is likely Jewish, states that “all souls are prepared for eternity, before the composition of the earth” (23:5), and later hints at Adam‘s preexistence (chap. 32). In a passage that may be laced with Greek influences, Josephus records that the Essenes, who denigrated the body, believed that “the soul is immortal and imperishable. Emanating from the finest ether, these souls become entangled, as it were, in the prison house of the body, to which they are dragged down by a sort of natural spell” (JW 2.8.11). Later rabbinic writers, as well as Philo of Alexandria, also held to this teaching.