G. Reale, A History of Ancient Philosophy: The Schools of the Imperial Age, trans. John R. Catan (Albany: State University of New York Press, 1990) 72.
The following are quotes from Musonius Rufus (30 C.E.-101 C.E.), whom Reale claims was influenced by Middle Platonism:
In general, man alone among terrestrial beings is an image of God[,] he has virtues similar to him, because not even among the Gods can we suppose anything superior to prudence, to justice, and even to courage and temperance. And as God, by the presence of these virtues, is victorious over pleasure and victorious over immoderation, he is superior to the passions and to envy and jealousy, magnanimous, loving towards man (because it is of such a nature that we imagine God to be); in this way we think that man, who is the image of him, when living according to nature is in the same condition as God, and in this way he is enviable: being enviable, he will himself also be happy, because we only envy the happy.
Your father forbids you to philosophize, but the father of all, men and Gods, Zeus, commands you and imposes it on you. His order, his law is that man be just, noble, beneficent, sober, magnanimous, above fatigue, above pleasures, free of all envy and all deception: to speak briefly the law of Zeus commands all men to be good human beings.
To be honest, this is the second time that I'm reading this book, since I didn't fully comprehend it the first time around. I read that the Middle Platonists believed in man becoming like God, but I didn't know what they meant by that. Did they conceive of God as a personal being? It turns out that they did, and they exhorted people to imitate the gods in virtue, self-control, and happiness.
I've often read that certain philosophers did not like Homer's depiction of the gods, which made them out to be like humans: wrathful, lustful, jealous, etc. That's why they treated Homer as an allegory rather than taking his accounts of the gods literally. What's interesting is that Musonius views Zeus as virtuous, which tends to contradict some of the myths about the gods, and yet he doesn't seem to think that virtue is automatic to the gods. He claims that the gods are "victorious" over pleasure and immoderation. Does that mean that they have desires like humans, yet they have managed to conquer them?
Christianity has this sort of concept because it believes in a God who became a man, Jesus Christ. According to Hebrews, Jesus was tempted in every manner as we are, yet without sin, and he also became perfect through suffering (Hebrews 2:10; 4:15; 5:9).