Aliya Summary: Moshe prayed to G‑d, and the frogs all died. Egypt reeked from the odor of rotting frogs, and Pharaoh reneged on his promise. Plague Three: Aaron smote the earth with his staff, and swarms of lice attacked Egypt, covering man and beast. Even Pharaoh’s magicians were amazed by this, and informed Pharaoh that this is the “finger of G‑d.” Plague Four: G‑d dispatched Moshe to warn Pharaoh that his land will be infested by a mixture of noxious animals. Only the land of Goshen, where the Israelites lived, would be spared.
While the Jews did not suffer from the plagues that were thrust on the Egyptians, the first time that became abundantly clear was with the fourth plague, Arov, because an entire Jewish city was excluded. It helped solidify the message Moshe was delivering with each plague: That the true G-d is controlling everything, not Paroh or any of his gods. It seems that this was conveyed in progression: Paroh’s magicians were able to turn water to blood, but not to the extent that G-d did. Same with frogs. With lice, however, his magicians finally broke the news to Paroh, that this is the work of G-d (8:15). The fourth plague now clarifies that the true G-d favors the Jews. It’s fascinating that Paroh was presented with these revelations in the order which he needed to process them, rather than forcing his hand right away. This Aliya (and exodus in general) is all about respecting the human process (even evil humans).