Why Balak Trembled When He Saw What Israel Did to the Amorite

(Numbers 22:2) "AND BALAK SAW." He saw the retribution that Israel had inflicted upon the Amorite. It would be better for the wicked to be blind, for their eyes bring a curse upon the world. In the generation of the Flood [it is written], "And the sons of God saw the daughters of men, etc." (Genesis 6:2). And [it is written], "And Ham, the father of Canaan, saw, etc." (Genesis 9:22). And [it is written], "And the officials of Pharaoh saw her, etc." (Genesis 12:15). And [it is written], "And Shechem son of Hamor saw her, etc." (Genesis 34:2). And likewise [here], "And Balak saw." A parable: It is like one who set guards to guard him from the marauding band, and he was confident in them because they were mighty men. The band passed through and killed them, and he trembled for himself. So too Balak: he saw what was done to Sihon and Og, to whom he had been paying tribute to guard him, and he was afraid for himself. And furthermore, he saw the miracles of the wadis of Arnon.