Moses
Exodus 7:3BSB·traditional attribution

But I will harden Pharaoh’s heart, and though I will multiply My signs and wonders in the land of Egypt,

John Calvin Reformed @genevareformer

3. And I will harden. As the expression is somewhat harsh, many commentators, as I have before said, take pains to soften it. Hence it is that some take the words in connection, “I will harden Pharaoh’s heart by multiplying my signs;” as if God were pointing out the external cause of his obstinacy.

Matthew Henry Presbyterian @wholebiblehenry

Here, I. God encourages Moses to go to Pharaoh, and at last silences all his discouragements. 1. He clothes him with great power and authority (Exo 7:1): I have made thee a god to Pharaoh; that is, my representative in this affair, as magistrates are called gods, because they are God's viceregents.

Commenting on Exodus 7:1-7

John Gill Reformed Baptist @doctorgill

And I will harden Pharaoh's heart,.... See Gill on Exo 4:21. and multiply my signs and my wonders in the land of Egypt; work one miracle and wonderful sign after another, until they are all wrought intended to be wrought; and which he had given Moses power to do, and until the end should be answered and obtained, the letting go of the children of Israel.