Exodus 10:12

“And the Lord said unto Moses, stretch out thine hand over the land of Egypt, etc.] First one way, and then another, towards every quarter, and every part of the land, to signify that the following plague would come upon the whole land: for the locusts, that they may come up upon the land of Egypt; the stretching out of his hand was to be the signal to them to come up and spread themselves over the land, which was brought about by the mighty power of God; for otherwise there was no such virtue in the hand or rod of Moses, to have produced so strange an event: and eat every herb of the land, even all that the hail hath left; the wheat and the rye, or rice, the grass, herbs, and plants, it had…”

“Stretch: Exo 7:19 eat every: Exo 10:4, Exo 10:5 Exodus 10:13”

“After His messengers had been thus scornfully treated, Jehovah directed Moses to bring the threatened plague upon the land. "Stretch out thy hand over the land of Egypt with locusts;" i.e., so that the locusts may come. עלה, to go up: the word used for a hostile invasion. The locusts are represented as an army, as in Joe 1:6. Locusts were not an unknown scourge in Egypt; and in the case before us they were brought, as usual, by the wind. The marvellous character of the phenomenon was, that when Moses stretched out his hand over Egypt with the staff, Jehovah caused an east wind to blow over the land, which blew a day and a night, and the next morning brought the locusts ("brought:" inasmuch…”