[As Adam] slept a rib was taken from him and the woman, Eve, was created. There is no doubt that this first man Adam before he sinned typified the Redeemer. For as the Redeemer slept in the stupor of suffering and caused water and blood to issue from his side, he brought into existence the virgin and unspotted church, redeemed by blood, purified by water, having no spot or wrinkle, that is, washed with water to avoid a spot, stretched on the cross to avoid a wrinkle.This analogy (Adam's rib:Eve :: Christ's side: His Bride the Church) is delightful, and for me novel. Indeed, much as the aqedah (Abraham's sacrifice of Isaac) really makes sense only in light of God's sacrifice of His Own Son (on the same mountain, some say), so the conjugal union of Adam and Eve as prefigurement of Christ and the Church makes sense of what otherwise seems a rather odd and unmotivated part of the Creation story. In both cases, what looks arbitrary and absurd in the Hebrew Bible taken alone looks artful and profound when placed in the Bible's key context: Christ.
For forty years... the Israelites dwelt in the desert and familiarized themselves with their laws, and lived on the food of the angels. Once they had assimilated the Law, they crossed the Jordan with Joshua and were given permission to enter the Promised Land.St. Paul often inverts Old Testament dichotomies so that, e.g., instead of Isaac standing for Israel and Ishmael for the gentiles, Paul, contra the literal genealogies, has Ishmael stand for Israel, and Isaac for the Christian Church. Something similar might be in Gregory's mind here. As we know, of all the Old Testament figures from whom Christ might've taken His name, He chose to be born with the name of Joshua (identical to Jesus when both are in the Aramaic or Hebrew). And Joshua is the conqueror, who, like Christus Victor, leads the people beyond what Moses can give them and into the Promised Land. And so in Gregory, we see that the Law had to be assimilated before the people were ready for Joshua to lead them into the Promise. And this is precisely how Christianity views Jewish monotheism: as a legalistic particularism necessary to build up enough awe of the One God distinct from pagan idols, such that when Christ came, His identity would be a Trinitarian shock, and not merely assimilated to some local pantheon like a Dionysus or Krishna figure. And thus, we have the long years of "assimilating the Law" identified, in Pauline fashion, not with the Promised Land, but with the wandering in the desert that needed to precede it.