God is the ultimate “Punisher”. But He sends His “angel of death” to bring the punishment about.
We can confirm this by the words elsewhere in Scripture:
Exodus 3:20 For I will stretch forth my hand and will strike Egypt with all my wonders which I will do in the midst of them: after these he will let you go.
Exodus 12:12 And I will pass through the land of Egypt that night, and will kill every firstborn in the land of Egypt both man and beast: and against all the gods of Egypt I will execute judgments: I am the Lord…23 For the Lord will pass through striking the Egyptians: and when he shall see the blood on the transom, and on both the posts, he will pass over the door of the house, and not suffer the destroyer to come into your houses and to hurt you.
I hope that helps.