asking:

I have a question about Exodus and the Red Sea crossing. Why does God make a point of saying He will "harden the hearts" of both Pharaoh and the Egyptians so that they will chase them? It says multiple times that he will harden their hearts or "make them obstinate". Why is this? Is it a poetic way of saying their hearts are hardened because that's just how they are and God knows that, or is it actually something God did to them in an active way? I'm troubled by this because it makes it sound like the Egyptians might not have chased them, and might not have died, without God's changing their hearts in some way. Like God condemns the Egyptians to die when they don't deserve it. What does the Church say about passages like this? Can you help me?

One of the things to always bear in mind about the Old Testament is that, while it is inspired by God and his Spirit is the principle Author, nonetheless, as 1 Peter puts it, "The prophets who prophesied of the grace that was to be yours searched and inquired about this salvation" (1 Peter 1:10). Likewise, Paul tell us that the fullness of revelation was " not made known to the sons of men in other generations as it has now been revealed to his holy apostles and prophets by the Spirit" (Ephesians 3:5). And Jesus likewise makes clear that "many prophets and righteous men longed to see what you see, and did not see it, and to hear what you hear, and did not hear it. (Matthew 13:17). So Matthew says that Jesus uttered "what has been hidden since the foundation of the world.” (Matthew 13:35)

All of which is to say that the biblical authors are themselves struggling to understand the meaning of the revelation they themselves reveal. One of the things they struggle with is how to describe the relationship of God with the sin and evil we commit. On the one hand, they know God is sovereign. On the other hand, they know he is good. And so one of the ways the ancient Israelite mind speaks is of God "hardening" Pharaoh's heart. But we must always read such texts in light of the fulness of revelation we have received in Christ, which shows us that God never ever wills for any person to do evil and never compels anybody to do what is sinful:

Let no one say when he is tempted, “I am tempted by God”; for God cannot be tempted with evil and he himself tempts no one; but each person is tempted when he is lured and enticed by his own desire. Then desire when it has conceived gives birth to sin; and sin when it is full-grown brings forth death. (James 1:13-15).

So Exodus is not saying, "God needed a villain for the story of Exodus, so he magicked Pharaoh, who was actually a really nice guy, into hardening his heart, like in those movies when an evil magician turns somebody into a zombie who does horrible things against his will, or when Jean-Luc Picard is taken over by the Borg and can't stop himself from destroying the Federation fleet." God never wills evil and never wills that we do it either.

So what is Exodus getting at? Well, it's getting at the fact that God, not we, is the center of the story and that he will go on being and doing what he is and does. There's no point in the wet clay telling the fire to change its nature. Fire will go on being and doing what it is and does, and our God is a consuming fire. If the wet clay wifully confronts the fire, the wet clay will become hard, not because the fire is putting mind control whammy on the clay, but because the fire is what it is. Pharoah's heart is hardened by his confrontation with God, not because God gave him no chance to repent, but despite the fact that God gave him ten chances to repent and he wilfully refused each time.