Why God sent Moses to drive out the people of Israel from the bondage of Egypt and He also hardened Pharaoh’s heart to send later the 10 plagues?
To make Himself known to the Egyptians
From the very beginning, when He sent Moses to drive out the people of Israel from the Egyptian slavery, God told Moses that He would harden Pharaoh’s heart and what was His reason for that:
Then the LORD said to Moses, “See, I make you as God to Pharaoh, and your brother Aaron shall be your prophet. You shall speak all that I command you, and your brother Aaron shall speak to Pharaoh that he let the sons of Israel go out of his land. But will harden Pharaoh’s heart that I may multiply My signs and My wonders in the land of Egypt. When Pharaoh does not listen to you, then I will lay My hand on Egypt and bring out My hosts, My people the sons of Israel, from the land of Egypt by great judgments. The Egyptians shall know that I am the LORD, when I stretch out My hand on Egypt and bring out the sons of Israel from their midst.” (Exodus 7:1-5)(NASB)
So, the purpose for which God had to harden Pharaoh’s heart was just to make the 10 wonders in Egypt and the people of that country, who were overly idolatrous, may see the power of God and worship Him.
To be always honored by the people of Israel
This is another reason why God hardened Pharaoh’s heart, as it is said below:
Then the LORD said to Moses, “Go to Pharaoh, for I have hardened his heart and the heart of his servants, that I may perform these signs of Mine among them, and that you may tell in the hearing of your son, and of your grandson, how I made a mockery of the Egyptians and how I performed My signs among them, that you may know that I am the LORD.” (Exodus 10:1-2)(NASB)
That the glory of God may be revealed
When they were in front of the Red Sea, threatened by Pharaoh’s army, God said to Moses one more reason for which He had hardened Pharaoh’s heart:
As for you, lift up your staff and stretch out your hand over the sea and divide it, and the sons of Israel shall go through the midst of the sea on dry land. As for Me, behold, I will harden the hearts of the Egyptians so that they will go in after them; and I will be honored through Pharaoh and all his army, through his chariots and his horsemen. Then the Egyptians will know that I am the LORD, when I am honored through Pharaoh, through his chariots and his horsemen. (Exodus 14:16-18)(NASB)
Translated by Felicia Rotaru