This difference we have identified between Jacob and Joseph is essential to the story that will unfold, for whether Joseph is a better or worse theologian than his father, his habits of mind are essential to the calling he will assume, the vocation of saving his family.
Again in this opening chapter, Joseph reflects on his name and the important fact that it contains the word sepher (or sefer), which means book or scroll or document. “He loved composing with the stylus and was so skilled at it that he could have served as a junior scribe at some place where documents were collected” (68).
Later, after his brothers sell him into slavery and he finds himself in Egypt, working in the household of a rich and powerful man named Petephrê (Potiphar), he actually becomes a scribe, and Petephrê’s overseer, Mont-kaw, contemplates this boy:
And here Joseph stood before him, scroll in hand, and, for a slave, even a scribal slave, he spoke clever, rougishly subtle words — and that combination of ideas was unsettling. This young Bedouin and Asiatic did not have the head of an ibis on his shoulders, and was, needless to say, a human being, not a god, not Thoth of Khmunu. But he had intellectual connections with that god, and there was something ambiguous about him…. 
Again and again in the tetralogy Joseph is associated with the Egyptian god Thoth. Thoth was the god of writing, of communication; he was also a wise counselor and mediator, and a messenger. In a story Socrates tells in Plato’s Phaedrus, Thoth offers the gift of writing to one King Thamus, who rejects it. When the Greeks learned about Thoth they immediately recognized him as a version of Hermes, or rather — since they were often inclined to see themselves as inheritors of Egyptian wisdom — recognized Hermes as a version of Thoth.
At several key points in the story Joseph encounters a nameless figure who is a guide — especially a guide to the Underworld that is Egypt — and a messenger. This is clearly Thoth/Hermes. Maybe I’ll write about him in a later post. But right now I am concerned with Joseph’s own Thothness: what he ultimately becomes is the go-between, the messenger, the mediator, who links his family — his radically monotheistic nomadic-shepherd family — with the great Egyptian empire, full of magnificent cities and temples and a near-infinity of gods. Only Joseph can mediate those two worlds.
For much of the book, I assumed that in telling Joseph’s story Mann was essentially writing a critique of monotheism, at least in its Israelite form; that he was teaching us that Joseph’s flexible and quasi-syncretic way is the better way. But eventually I was forced to reconsider that view.