Hardening Pharaoh's Heart
Metaphorically Pharaoh's contest with God is like a man wrestling with a bear. The man has a choice whether to engage in the match but the bear decides when it is over.
New Testament is the New Evidence
The New Testament is the evidence that God has kept the promises and prophecies that He made in the Tanak. Hence, the idea that the New Testament introduces some new theology is unsound.
When Hospitality Leads to Slavery
By the end of Genesis, Israel is no longer free to leave Egypt. They aren't yet slaves, but neither are they free. This echoes the experience of Jacob with his uncle Laben.