there is an abundant scholarly literature discussing the influence of ancient philosophy on the thinking of Paul.
Troels Engberg-Pedersen: Paul and the Stoics
Th. D. Niko Huttunen: Paul and Epictetus on Law
Abraham J. Malherbe: Paul and the Popular Philosophers
Engberg-Pedersen sees remarkable similarities between the Stoic concept of Logos/Reason and Paul’s concept of Christ as a life-changing power, specifically “from above”, “in whom” the convert dwells. (Compare the expressions “in Christ”, “Christ in you”.)
Huttunen argues for Paul’s debt to Stoicism for much of his theological teachings about the law. (This Stoic model was indebted ultimately to Plato and his discussion of ethics and the good life in his Republic.)
Modern scholarship was not the first to discover Paul’s indebtedness to Greek culture. His letters, even on a superficial level, have many affinities with the popular philosophy of his day, especially as it was represented by Stoicism and Cynicism. . . .
During the last hundred years, New Testament scholars have shown that many aspects of Paul’s life and letters are illuminated with they are examined in the light of Greco-Roman culture. There can no longer be any doubt that Paul was thoroughly familiar with the teaching, methods of operation, and style of argumentation of the philosophers of the period, all of which he adopted and adapted to his own purposes. . . .
The points of similarity between Paul and his philosophic competitors may be stressed to the point that he is viewed as a type of hellenistic philosopher. (pp. 67-68)
Peter, Paul, and Mary Magdalene, pp. 103, 107:
[A]s a Jew in the Diaspora, Paul would have been surrounded by people embracing religions other than Judaism. Paul, unlike Jesus or Peter, was raised in a non-Jewish, “pagan” environment. . . .
Paul actually came from a Greek-speaking, rather than Aramaic speaking, environment. . . . It is clear that Paul must have come from some relatively large urban setting in the Jewish Diaspora, and this may have been Tarsus. . . . Tarsus was known as one of the great philosophical centers of the empire, one of the two or three best places for a person to develop his philosophical and rhetorical abilities. . . .
The mystery cults were relatively distinct in focusing chiefly on the well-being of the individual. Moreover, whereas almost all other religions were centered on life in the here and now, mystery cults appear to have placed some emphasis (older scholarship believed it was exclusive emphasis) on providing a happy existence in the life after death. . . .
The mysteries, it appears, met personal, individual needs and resonated with many persons in the Greco-Roman world who did not find existential fulfillment (to use a modern phrase) in the local and state cults in which they participated. Each of the mystery cults was different; each had its special location and its own customs and rituals. Many of them evidently centered around a mythology of the death and resurrection of a god or goddess, a mythology ultimately rooted in ancient fertility religion, in which the death of winter gives way to the new life of spring. Moreover, the periodic ritual of these cults apparently celebrated this mythology in a way that enabled the participants to become part of the entire transformative process of new life. That is to say, the enacted myth about the gods was transmuted into reality for the devotees, who believed those who had been found worthy to be a follower of the mystery’s god or goddess, there was promised not only a more satisfying existence now but also a more blissful afterlife.
Not just anyone could walk in off the streets to join one of these mystery cults. Each of them appears to have emphasized rituals of initiation for membership. Those who wished to join were typically put through a period of ceremonial cleansing (involving fastings, prayers, and sometimes ritual washings) and instruction prior to being admitted to the ranks of the devotees. We have evidence to suggest that those who had experienced the initiation, who could then join in the ceremonies when they were periodically celebrated, felt at greater peace with themselves and the world. (My emphasis. Excerpted from ‘The New Testament: A Historical Introduction To The Early Christian Writings’ by Bart D. Ehrman, Oxford University Press, 2000, pp. 28-31; p. 33 of the 2004 3rd edition — and thanks again to the reader who alerted me to this publication of Ehrman’s)
Scholars in the earlier part of this century were struck by how similar the ancient descriptions of the mysteries were to what we know about Christianity; for it too was a secretive society whose members worshiped a divine being who died and was raised from the dead, and who could bring peace on earth and eternal life after death. Initiates into the society went through a period of ritual purification (baptism) and instruction, and members, according to this view, periodically celebrated the myths of the cults beginning (in the Lord’s Supper).
Recent scholarship, however, has been less inclined to call Christianity a mystery cult, or to claim that it simply borrowed its characteristic ideas and practices from previously existing religions. In part this is because we do not know very much about what happened during the mystery rituals., especially in the period when Christianity began. For example, did they typically partake of a meal, commemorating the death of their savior god? We simply don’t know.
All the same, the broad parallels between Christianity and these other religions do remain intriguing and worthy of reflection. Maybe the question scholars have asked should be posed differently: would non-Christian outsiders have looked upon Christianity as a kind of mystery cult, analogous to others that they knew?
christianity combines jewish atonement ideas with pagan dying and rising gods.
No competent mythicist makes this claim. Rather, they claim that virgin-born gods were a common phenomenon in the region at the time and dying-and-rising gods were a common phenomenon in the region at the time (in precisely the way these were not anywhere else, e.g. in ancient China), and so for Jews to suddenly start claiming they have one, too, looks pretty easily explained in terms of standard theories of cultural diffusion. (See my chapter on the origins of Christianity in The End of Christianity, ch. 2, pp. 53-74.)
Christianity therefore certainly was as well (it would go against all prior probability to claim otherwise, and against all the evidence as well). Judaism had a prominent component of sacrifices atoning for a nation’s entire sins, a belief in the holy spirit making Jewish kings into the sons of god (see Not the Impossible Faith, chapter 9), and a tendency toward ascetic denigration of sexuality. Paganism had a prominent component of dying-and-rising savior gods, who likewise offered ways to cleanse their followers of sins and thus procure them entry into paradise–not necessarily by their death, but always in some way, and in many cases through baptismal rituals long predating Christianity’s adoption of the same or similar ritual (see The Empty Tomb, p. 215, n. 210); and pagans had many traditions about virgin born sons of god. Note what happens when you combine the Jewish side with the pagan: you get Christianity. This is actually almost certainly what happened, and thus should not even be in dispute.
What “Inanna or Zalmoxis or Bacchus or Adonis and so on; Osiris” etc. (Romulus as well) illustrate is a common mytheme: a son of god who dies and is resurrected. This is a mytheme not found anywhere else (like China). It is therefore a cultural peculiarity of the ANE and Mediterranean. That is why it would be an extremely improbable coincidence if Jews started claiming to have one of those and didn’t get the idea from that cultural fad. Down right impossible, in fact; the probability of such a coincidence is that low.
Notably, this is clearly a fad (so many resurrected sons of god in this era and region; zero in any other cultural regions, like China), yet all these gods are different from each other in many ways; yet many also share improbable similarities (e.g. Osiris, Romulus, and Bucchus were all torn apart, a very unusual way to die or be disposed of; thus it is extremely improbable that this idea didn’t migrate by diffusion among them–the most likely pathway is Osiris belief influenced Bacchus belief through Greek contact with Egypt, then Bacchus belief influenced Romulus belief through Italian contact with Sicily and Magna Graecia). No one finds that a dubious hypothesis; everyone agrees it’s pretty obvious. But the moment you suggest any such thing for Jesus, everyone gets all in a rage, like ‘ol handless Luke Skywalker, “No!!! That’s not true! That’s imposssssibbble!”
When you read what Mettinger’s actual analysis says (and not that final paragraph), he meticulously proves that the mytheme of dying-and-rising gods actually existed at least a thousand years before Christianity, that it was reproduced in several cults across the region, and that all attempts to argue otherwise are baseless.