Exodus 3:20 KJV
And I will stretch out my hand, and smite Egypt with all my wonders which I will do in the midst thereof: and after that he will let you go.
Exodus 3:20, King James Version
In context
19 And I am sure that the king of Egypt will not let you go, no, not by a mighty hand.
20 And I will stretch out my hand, and smite Egypt with all my wonders which I will do in the midst thereof: and after that he will let you go.
21 And I will give this people favour in the sight of the Egyptians: and it shall come to pass, that, when ye go, ye shall not go empty: