Then the LORD said to Moses, “Stretch out your hand toward heaven, so that there may be hail in all the land of Egypt, on man and beast and every plant of the field, in the land of Egypt.”
22. And the Lord said. The rod of Moses is again employed to bring on the storm, not so much for Pharaoh’s sake, as that Moses may be the more encouraged to the remaining contests, when he sees the proof of his vocation renewed.
The threatened plague of hail is here summoned by the powerful hand and rod of Moses (Exo 9:22, Exo 9:23), and it obeys the summons, or rather the divine command; for fire and hail fulfil God's word, Psa 148:8. And here we are told, I. What desolations it made upon the earth.
Commenting on Exodus 9:22-35
And the Lord said unto Moses,.... When the morrow was come, the fifth day of the month Abib: stretch forth thine hand toward heaven; with his rod in it, as appears from the next verse, to show that the following plague would come from the heaven, that is, the air, and from God, who dwells in the heaven of heavens: that there may be hail...