Just finished Ancient Greece: From Prehistoric to Hellenistic Times (Yale Univ Press, 1996) by Thomas R. Martin. The book is a nice overview of Greek history and culture. After reading A War Like No Other, I wanted to "fill in the gaps" and see how the carnage of the Peloponnesian War gave rise to Alexander and his conquest of the East. And, after reading Between the Testaments, I wanted to see how Greek religion and philosophy, as mediated by Hellenistic culture, contributed to developing Christianity. The omission of the Apocrypha from modern bibles and the modern Christian (and Mormon) consciousness works to suppress the Greek influence; it takes a little work to find it, but it's definitely there.
Religion first. Moderns tend to ignore Greek religion, making them out to be modern secularists before their time, full of poetry, literature, philosophy, and politics. Sorry, the Greeks were quite religious. The Parthenon, of course, was a temple dedicated to Athena, the patron goddess of Athens, a huge image of whom graced the interior of the temple in its day. Not offending the gods was always a central concern of Greek civic life (recall that Socrates was convicted of impiety by an Athenian jury, and that the Spartans were not at Marathon to fight the invading Persians because they weren't allowed to leave the city during a religious festival!). Socrates, not generally considered a religious fellow, found his life's inspiration from counsel relayed to him by the Oracle at Delphi, followed guidance given him by a personal daemon (whispering spirit or guardian angel) over the course of his life, and gave a last request to his friends that they satisfy (on his behalf) a debt he owed to Asclepius, the Greek god of healing.
One feature of Greek religion was the oracles, religious shrines where priestesses pledged to serve the god of the shrine (and trained for such duty) would respond to the offerings and inquiries of pilgrims and civic envoys with conveniently ambiguous but vaguely encouraging responses, like the sort of sayings you get inside fortune cookies. The counsel to Socrates, for example, was "You are the wisest of all men." There's a parallel to how Israelite prophets acted as oracles for the Israelites, except that the Israelite prophets provided a lot of social and moral counsel and reproof to Israelite leaders, whereas the Greek oracles just sucked up to the paying pilgrim or patron. Christianity did well to follow the Israelite form of oracular wisdom rather than the Greek form.
Another offshoot of Greek religion were the activities associated with religious festivals, such as Greek drama (which grew out of productions staged during the spring festival of Dionysus at Athens) and the Olympic Games (which accompanied a religious festival honoring Zeus). But neither drama nor the gymnasium were welcomed or emulated by Jews or Christians. Coming up short so far.
Greek religion also featured popular and revered mystery cults such as the Eleusinian Mysteries. Here's what the book says about what these mysteries were and how the whole thing worked:
Prospective initiates participated in a complicated set of ceremonies that culminated in the revelation of Demeter's central secret after a day of fasting. The revelation was performed in an initiation hall constructed solely for this purpose. ... The most eloquent proof of the sanctity attached to the Mysteries of Demeter and Kore is that throughout the thousand years during which the rites were celebrated, we know of no one who ever revealed the secret. To this day, all we know is that it involved something done, something said, and something shown. It is certain, however, that initiates expected to fare better in their lives on earth and also were promised a better fate after death.
Christianity didn't incorporate any of this mystery religion stuff, although some might think Mormonism has (rather indirectly). If there had been an Internet in the days of the Greeks, I'm sure we'd know all about the Eleusinian Mysteries. In any case, the bottom line seems to be that very little of Greek religion per se is evident in early Christianity. That wasn't really where I was going with this discussion, but that's where I've ended up. There was the Greek language, of course (koine, the working Greek of the East), which was the language of the New Testament, of Stephen, of Paul, and probably of Jesus. And you might argue that Greek religious sensibility helps explain how well early Christianity was received in the Greek cities of the East where it really blossomed. But that's about it for Greek religion.
Greek philosphy fared better. Neoplatonism, expanding on Plato's mystical side, had a powerful influence on Christian theologians of the third and fourth centuries. The Greek concepts of substance and attribute were central to defining the Christian God in general and the Christian Trinity of the creeds. Ironic that Christianity ignored Greek religion but appropriated Greek philosophy, which owed its popularity to the Greek belief that the world should be rational as well as divine. I think Christianity picked up this general Greek sense of Greek rationality as well as its specific concepts and arguments of Neoplatonism. So I'll wind up with a paragraph from the book summarizing the effect of the Presocratics and explaining how this rational sense originated:
Developing the view that people must give reasons to explain what they believe to be true, rather than just make assertions that they expect other to believe without evidence, was the most important achievement of the early Ionian thinkers. This insistence on rationality, coupled with the belief that the world could be understood as something other than the plaything of divine whim, gave human beings hope that they could improve their lives through their own efforts. As Xenophanes put it, "The gods have not revealed all things from the beginning to mortals, but, by seeking, human beings discover, in time, what is better." Xenophanes, like other Ionian thinkers, believed in the existence of gods, but he nevertheless assigned the opportunity and the responsibility for improving human life squarely to human beings themselves. Human beings themselves were to "discover what is better."