Exodus 3:19 in the King James Version
And I am sure that the king of Egypt will not let you go, no, not by a mighty hand.
Context
18 They will listen to your voice. You shall come, you and the elders of Israel, to the king of Egypt, and you shall tell him, ‘The LORD, the God of the Hebrews, has met with us. Now please let us go three days’ journey into the wilderness, that we may sacrifice to the LORD, our God.’
19 I know that the king of Egypt won’t give you permission to go, no, not by a mighty hand.
20 I will reach out my hand and strike Egypt with all my wonders which I will do among them, and after that he will let you go.