Exodus 3:19

But I myself know that the king of Egypt will not allow you to go {unless compelled by a strong hand}.

Exodus 5:2

And Pharaoh said, "Who is Yahweh that I should listen to his voice to release Israel? I do not know Yahweh, and also I will not release Israel."

Exodus 6:1

And Yahweh said to Moses, "Now you will see what I will do to Pharaoh, because with a strong hand he will release them, and with a strong hand he will drive them out from his land."

Exodus 7:1-14

And Yahweh said to Moses, "See, I have made you [as] a god to Pharaoh, and Aaron your brother will be your prophet.

Psalm 136:11-12

And he brought Israel out from among them, for his loyal love [endures] forever.

Isaiah 63:12-13

{who made} his magnificent arm move {at} the right hand of Moses, {who divided} [the] waters {before them}, to make an everlasting name for himself,

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 Yahweh that I should listen to his voice to release Israel? I do not know Yahweh, and also I will not release Israel."
Exodus 7:4
And Pharaoh will not listen to you, and I will put my hand into Egypt and bring out my divisions, my people, the {Israelites}, from the land of Egypt with great punishments.

No, not by a mighty hand

Exodus 6:1
And Yahweh said to Moses, "Now you will see what I will do to Pharaoh, because with a strong hand he will release them, and with a strong hand he will drive them out from his land."
Psalm 136:11
And he brought Israel out from among them, for his loyal love [endures] forever.
Isaiah 63:12
{who made} his magnificent arm move {at} the right hand of Moses, {who divided} [the] waters {before them}, to make an everlasting name for himself,