20 Then the Lord said to Moses, “Rise up early in the morning and present yourself to Pharaoh, as he goes out to the water, and say to him, ‘Thus says the Lord, “Let my people go, that they may serve me. 21 Or else, if you will not let my people go, behold, I will send swarms of flies on you and your servants and your people, and into your houses. And the houses of the Egyptians shall be filled with swarms of flies, and also the ground on which they stand. 22 But on that day I will set apart the land of Goshen, where my people dwell, so that no swarms of flies shall be there, that you may know that I am the Lord in the midst of the earth.[e] 23 Thus I will put a division[f] between my people and your people. Tomorrow this sign shall happen.”’” 24 And the Lord did so. There came great swarms of flies into the house of Pharaoh and into his servants’ houses. Throughout all the land of Egypt the land was ruined by the swarms of flies.
25 Then Pharaoh called Moses and Aaron and said, “Go, sacrifice to your God within the land.” 26 But Moses said, “It would not be right to do so, for the offerings we shall sacrifice to the Lord our God are an abomination to the Egyptians. If we sacrifice offerings abominable to the Egyptians before their eyes, will they not stone us? 27 We must go three days’ journey into the wilderness and sacrifice to the Lord our God as he tells us.” 28 So Pharaoh said, “I will let you go to sacrifice to the Lord your God in the wilderness; only you must not go very far away. Plead for me.” 29 Then Moses said, “Behold, I am going out from you and I will plead with the Lord that the swarms of flies may depart from Pharaoh, from his servants, and from his people, tomorrow. Only let not Pharaoh cheat again by not letting the people go to sacrifice to the Lord.” 30 So Moses went out from Pharaoh and prayed to the Lord. 31 And the Lord did as Moses asked, and removed the swarms of flies from Pharaoh, from his servants, and from his people; not one remained. 32 But Pharaoh hardened his heart this time also, and did not let the people go.
9:1 Then the Lord said to Moses, “Go in to Pharaoh and say to him, ‘Thus says the Lord, the God of the Hebrews, “Let my people go, that they may serve me. 2 For if you refuse to let them go and still hold them, 3 behold, the hand of the Lord will fall with a very severe plague upon your livestock that are in the field, the horses, the donkeys, the camels, the herds, and the flocks. 4 But the Lord will make a distinction between the livestock of Israel and the livestock of Egypt, so that nothing of all that belongs to the people of Israel shall die.”’” 5 And the Lord set a time, saying, “Tomorrow the Lord will do this thing in the land.” 6 And the next day the Lord did this thing. All the livestock of the Egyptians died, but not one of the livestock of the people of Israel died. 7 And Pharaoh sent, and behold, not one of the livestock of Israel was dead. But the heart of Pharaoh was hardened, and he did not let the people go.
8 And the Lord said to Moses and Aaron, “Take handfuls of soot from the kiln, and let Moses throw them in the air in the sight of Pharaoh. 9 It shall become fine dust over all the land of Egypt, and become boils breaking out in sores on man and beast throughout all the land of Egypt.” 10 So they took soot from the kiln and stood before Pharaoh. And Moses threw it in the air, and it became boils breaking out in sores on man and beast. 11 And the magicians could not stand before Moses because of the boils, for the boils came upon the magicians and upon all the Egyptians. 12 But the Lord hardened the heart of Pharaoh, and he did not listen to them, as the Lord had spoken to Moses. (Exodus 8:20–9:12, ESV)