Augustine is rather ingenious in his interpretations of the Old Testament narratives. I have been reading very slowly through the City of God and have recently covered Augustine's interpretation of the Noahic Flood. Typology is growing into favor again in Protestantism, which may bode well or ill depending upon how it is done.
A friend of mine recently posted some brilliant typological thoughts that I briefly interacted with in the comments. I thought I'd air them here, and perhaps add some elaboration.
My friend identified the sons of Israel/Jacob with the seed of the Serpent and Joseph with the seed of the Woman in the epic struggle between the City of God and the City of Man so prominent in Genesis and throughout Biblical history. However, the relationship is more complicated, or at least complex, than some of the others, for instance, Cain and Seth.
Why complex? Well, Judah, who is a son of Israel who sells Joseph into slavery (indeed, is the catalyst for that decision, delivering Joseph out of the hands of his other brothers, who had murderous intent), who marries a foreign wife, but who also ends up siring the seed of the Promise and becoming a substitutionary intercessor for Benjamin on behalf of Jacob/Israel, who will die if Benjamin is not returned safely.
Interestingly, the story of Judah and Tamar has some tantalizing typological possibilities. Judah marries a foreign wife, thereby committing adultery against the Covenant family, a kind of apostasy or exile. Tamar's origins are not given, but there is Rabbinic commentary that assumes she is an Israelite, or a member of the Covenant family. She is also, in the narrative, a rejected bride. Perhaps Judah represents wayward Israel, of whom Paul speaks in Romans 9-11. Perhaps Tamar is the bride of Christ, the Church, whose righteous intervention in the world arrests the waywardness of Judah/Israel and brings him back into the Covenant family. Tamar is not necessarily a Gentile, but neither is the Bride of Christ--for all who are of Christ are True Israel. The Bride is of mixed origin in national identity (Jew and Gentile), but is without national origin in her priestly identity (Christ is of the order of Melchizedek). Tamar is intercessory for Judah through her sexuality--she takes him up on his obligation, which he refuses to give (not unlike Ruth with Boaz, through Boaz is willing; or even Zipporah when she takes the foreskin of Moses' son when he neglects to do so).
All of this is quite tentative, and I wouldn't stake any firm claim on what I've got here, since I've only begun to consider the possibilities. I hope some readers of mine might interact with what I've put forward in the hopes of separating the wheat from the chaff.