By now, the Lord said to Pharaoh, “I could have stretched out my hand and struck you and your people with a plague that would have wiped you off the earth.”
So why didn’t he?
Just kill all the Egyptians and get Israel out of there.
But God doesn’t hate the Egyptians. He just loved Israel more.
And besides, God has a purpose with all these plagues. The purposes have been expressed as the story has unfolded.
First, through His mighty power worked in the plagues, He wants Israel to know that He is, indeed, the Lord. It is their God, the God of the Hebrews, who is truly God and He is the one who is bringing them out of Egypt. He does not want to be mistaken for some Egyptian or other god (6:7). Second, he wants the Egyptians to know that He, the God of the Hebrews and not some Egyptian God, is bringing Israel out. He can manipulate the weather, nature, natural resources and catastrophe (7:5). Third, he wants the people of power, namely, the magicians, to acknowledge that the God of the Hebrews is greater than they are (8:19). Fourth, He wants them all to know that He is unique. There is no one on the earth, and no god in anyone’s pantheon, equal to Him (9:14). Fifth, He wants Pharaoh to know that his very being (Pharaoh’s) is not a happenstance of nature, but rather a deliberate “raising up” on the part of the Lord. In chapter twelve He will say that He wants all the gods of Egypt to be felled (judged) in the sight of their worshipers. There is only one God. He is the god of the Hebrews, and they and only they are His people.
In the end, God is not whoever you think He is, or whoever or whatever you want Him to be. God is who He is, and He does not change. Our task is to know Him as He is and yield to His will.