And I will harden Pharaoh's heart, and multiply my signs and my wonders in the land of Egypt...and the Egyptians shall know that I am the Lord....Ex. 7:3-5
And I will harden Pharaoh's heart, that he shall follow after them; and I will be honoured upon Pharaoh, and upon all his host; that the Egyptians may know that I am the Lord. 14:4
And I, behold, I will harden the hearts of the Egyptians, and they shall follow them: and I will get me honour upon Pharaoh, and upon all his host, upon his chariots, and upon his horsemen.14:17
I guess Pharaoh did not stand a chance of having "an open heart." Exodus is a fascinating book. I like to compare myself with the Israelites, after all, as a Christians we are His people.
It's especially comforting to read that God heard the cry of His people (Ex. 3:7-8) and came to their help. The story could have been much simpler though. Moses goes before pharaoh, shows him a sign, maybe two, that God sent him and his brother to deliver their people out of bondage, pharaoh gets scared, listens to God and lets the people go.
But not so. God has a purpose. He wants all the nations to know and to fear the great I am. I believe His purpose was accomplished, read Exodus 25:15. And I also believe that He wants to prove Himself to His own people, and that purspose too was accomplished, read Exodus 14:31.
We always want the simple way out of our burdens (I'm speaking especially on my behalf).
And it came to pass, when Pharaoh had let the people go, that God led them not through the way of the land of the Philistines, although that was near, for God said, Lest preadventure the people repent when they see war, and they return to Egypt. But God led the people about, through the way of the wildernes of the Red sea...Exodus 13:17-18
God knows His people (and by that I mean me). How often are we (me again) like the Israelites and tempted to go back to Egypt, to go back into the world because things seemed much simpler and easier. Fear sets in.
And Moses said unto the people, Fear ye not, stand still, and see the salvation of the Lord.....The Lord shall fight for you, and ye shall hold your peace. Ex. 14:14
We all know how that came about (Chapter 14:21--31). He is a victorious God, and if we let Him lead us, then we will be a victorious people. There's a hymn we often sing at church (God leads us along), and the chorus goes like this:
God leads His dear children along. Some thru the waters, some thru the flood, some thru the fire, but all thru the blood; Some thru great sorrow, but God gives a song, In the night season and all the day long.