Exodus 9

3 Moses now warns Pharaoh that He is about to strike them with more severe plagues. The following plagues would not just be irritants, but they would threaten the economic foundation of Egypt.
4 Again, God would protect the Israelites and what possessions they had. Now it is probable that at least some (or the majority) of the Egyptian herds would have been tended by Israelite slaves. The specificity of this plague would most likely have related to ownership rather than attendants.
5 As with the other plagues, God sets the timing and the forewarning. Thus, everyone who heard of it would know it was a miracle.
6 The extent and severity of this plague would also attest to its miraculous origin.
7 No explanation is given for Pharaoh's rational. Again, Pharaoh himself might not have been as severely affected as the rest of the Egyptians. True, he lost a great deal of wealth, but his vast resources may have made his personal lifestyle only slightly affected. If Pharaoh liked meat, he could have purchased it from the Israelites or from other countries.
8 The furnace might have been used to harden bricks or other earthenware. These things that were instruments of hardship for the Israelites would be the source of pain for the Egyptians.
10 Boils are painful and disgusting. To have them break out all over the body would hinder not only work, but would make life miserable. The beasts mentioned here would include not only livestock that the Egyptians would have obtained since the previous plague, but all other domesticated animals as well.
11 The magicians, who had been the primary critics of God and Moses, now could not longer appear before Moses. Not only were the boils hindering them, but they were also utterly humiliated. Their power had proven to be inadequate when placed alongside God's increasingly powerful displays.
12 Here is the first instance of God hardening Pharaoh's heart. God had broken Pharaoh with physical pain, and he probably would have released the Israelites to gain relief. However, it is evident that Pharaoh still did not reverence God. God enhances Pharaoh's unbelief to give him "supernatural" strength in the face of these increasingly dreadful circumstances.
15 Obviously, since God could kill all of the Egyptian livestock in a single day, He could have just as easily killed all the Egyptians.
16 God's purpose was not to kill the Egyptians, but to display His power against them. God, who often seems silent in human history, displayed Himself so that the whole world would recognize that He did exist and had control over all things.
17 Pharaoh's opposition to God's people was simply a symptom of his opposition to God.
19 God gave Pharaoh a choice. If Pharaoh had been convinced that God caused all the plagues up to this point he could prove his faith by bringing in all his servants and livestock before the predicted storm.
20 There were many Egyptians, especially those in Pharaoh's court, who knew all that had happened. To them, the evidence was clear: God was working, and Moses was God's spokesman. They immediately brought in their servants and animals from the field.
21 However, Pharaoh did not listen to Moses. It's impossible to know what Pharaoh was thinking. Perhaps he had convinced himself that the previous plagues were just coincidence. Perhaps Pharaoh would not be convinced by these "natural" phenomena. Perhaps Pharaoh was also incredulous about the severity of the predicted hailstorm. Sure, hail can be bad, but hail had never killed anyone.
24 The hail was accompanied by a great lightning storm (Exo 9:28).
25 Every exposed thing would have been crushed, frozen, or burned.
27 This is the first time Pharaoh confesses.
28 Pharaoh will not entreat God personally, instead he asks someone else to do it. When we truly acknowledge God, we must go to Him, fall before Him, and ask for forgiveness. Pharaoh's lack of submission shows that he had not truly decided to stop "sinning" (i.e., offending God).
29 God had already shown His power to control the waters, the land, insects, and diseases. He had now proven His ability to control the sky and weather. He was indeed proving Himself greater than all the so-called gods of Egypt. The individual gods presumably had control over specific aspects of nature.
30 While some of Pharaoh's servants had shown that they believed in God by heeding Moses' warning, they probably continued to worship their idols. To worship God means to worship nothing else except Him.
31 This hailstorm destroyed the early crops in Egypt, but not the late crops.
34 Again, Pharaoh had survived through so much that he was able to encourage his own heart again. His advisors and servants were able to gain resolve not to let their labor force depart. First, it was obvious that they needed help to rebuild, and second, they probably wanted opportunity to revenge their losses on the Israelites. Overall, they remained unimpressed by the miracles of God.