Exodus 3:19

But I know that the king of Egypt will not let you go, no, not by a powerful hand.

Exodus 5:2

And Pharaoh said, Who is Jehovah, to whose voice I am to hearken to let Israel go? I do not know Jehovah, neither will I let Israel go.

Exodus 6:1

And Jehovah said to Moses, Now shalt thou see what I will do to Pharaoh; for by a strong hand shall he let them go, and by a strong hand shall he drive them out of his land.

Exodus 7:1-14

And Jehovah said to Moses, See, I have made thee God to Pharaoh; and Aaron thy brother shall be thy prophet.

Psalm 136:11-12

And brought out Israel from among them, for his loving-kindness endureth for ever,

Isaiah 63:12-13

his glorious arm leading them by the right hand of Moses, dividing the waters before them, to make himself an everlasting name,

Treasury of Scripture Knowledge

Summary

And I am sure that the king of Egypt will not let you go, no, not by a mighty hand.

No, not by a mighty hand

Bible References

Will not

Exodus 5:2
And Pharaoh said, Who is Jehovah, to whose voice I am to hearken to let Israel go? I do not know Jehovah, neither will I let Israel go.
Exodus 7:4
And Pharaoh will not hearken unto you; and I will lay my hand upon Egypt, and bring forth my hosts, my people, the children of Israel, out of the land of Egypt by great judgments.

No, not by a mighty hand

Exodus 6:1
And Jehovah said to Moses, Now shalt thou see what I will do to Pharaoh; for by a strong hand shall he let them go, and by a strong hand shall he drive them out of his land.
Psalm 136:11
And brought out Israel from among them, for his loving-kindness endureth for ever,
Isaiah 63:12
his glorious arm leading them by the right hand of Moses, dividing the waters before them, to make himself an everlasting name,