Moses and Aaron are encouraged to go again to Pharaoh, 1-6. Their age, 7. Aaron's rod is turned into a serpent, 8-10. The sorcerers do the like; but their rods are swallowed up by Aaron's, 11, 12. Pharaoh's heart is hardened, 13. God's message to Pharaoh, 14-18. The river is turned into blood; and the consequent distress of the Egyptians, 19-25.
1 And the LORD said to Moses, "Behold, I have made you a god to Pharaoh, and Aaron your brother shall be your prophet. 2 You shall speak all that I command you, and Aaron your brother shall speak to Pharaoh, so that he sends the children of Israel out of his land. 3 And I will harden Pharaoh's heart and multiply my signs and my wonders in the land of Egypt. 4 But Pharaoh shall not listen to you, and I will lay my hand upon Egypt and bring forth my armies, my people the children of Israel, out of the land of Egypt by great judgments. 5 And the Egyptians shall know that I am the LORD when I stretch forth my hand upon Egypt and bring out the children of Israel from among them." 6 And Moses and Aaron did as the LORD commanded them. And they did so. 7 And Moses was eighty years old and Aaron eighty-three years old when they spoke to Pharaoh.
8 And the LORD spoke to Moses and to Aaron, saying, 9 "When Pharaoh speaks to you, saying, 'Show a miracle,' then you shall say to Aaron, 'Take your rod and cast it before Pharaoh,' and it shall become a serpent." 10 And Moses and Aaron went to Pharaoh and they did so as the LORD had commanded. And Aaron cast down his rod before Pharaoh and before his servants, and it became a serpent. 11 Then Pharaoh also called the wise-men and the sorcerers. And the magicians of Egypt also did in like manner with their enchantments. 12 For they each cast down his rod, and they became serpents, but Aaron's rod swallowed up their rods. 13 And he hardened Pharaoh's heart and he did not listen to them, as the LORD had said.
14 And the LORD said to Moses, "Pharaoh's heart is hardened. He refuses to let the people go. 15 Go to Pharaoh in the morning, behold, he goes out to the water, and you shall stand by the river's brink to meet him. And the rod which was turned to a serpent you shall take in your hand. 16 And you shall say to him, 'The LORD God of the Hebrews has sent me to you, saying, "Let my people go so that they may serve me in the wilderness. And behold, until now you would not hear." 17 Thus says the LORD: "In this you shall know that I am the LORD: behold, I will smite with the rod that is in my hand upon the waters which are in the river, and they shall be turned to blood. 18 And the fish that are in the river shall die, and the river shall be offensive in smell, and the Egyptians shall loathe to drink of the water of the river."'" 19 And the LORD spoke to Moses, "Say to Aaron, 'Take your rod and stretch out your hand upon the waters of Egypt, upon their streams, upon their rivers, upon their ponds, and upon all their pools of water, so that they may become blood and that there may be blood throughout all the land of Egypt, both in vessels of wood and in vessels of stone.'"
20 And Moses and Aaron did so, as the LORD commanded. And he lifted up the rod and smote the waters that were in the river in the sight of Pharaoh and in the sight of his servants. And all the waters that were in the river were turned into blood. 21 And the fish that were in the river died, and the river was offensive in smell, and the Egyptians could not drink of the water of the river. And there was blood throughout all the land of Egypt. 22 And the magicians of Egypt did so with their enchantments. And Pharaoh's heart was hardened, neither did he listen to them, as the LORD had said. 23 And Pharaoh turned and went into his house, neither did he regard this also. 24 And all the Egyptians dug all around the river for water to drink because they could not drink of the water of the river. 25 And seven days were fulfilled after the LORD had smitten the river.
Matthew Henry Commentary - Exodus, Chapter 7[➚]
[v.3-4] - As God had told Moses before, He will harden Pharaoh's heart (Exodus 3:19) and bring judgment upon Egypt (Exodus 3:20). These signs and wonders are also to be viewed as judgments, for so they are called in verse 4. These judgments are much like the golden vials of judgment given to the seven angels in Revelation, chapter 16. Another thing to note with these judgments is that they are quite possibly targeting specific Egyptian gods (see Numbers 33:4), which would send the message that God is the God of Gods, the Supreme Being, the Eternal and Self-Sufficient One. So, it is important for God to perform multiple judgments upon Egypt in order to show that He is capable of subduing all of the Egyptian gods.