Funny enough, I found something in Gloria Steinem’s Outrageous Acts and Everyday Rebellions that may give some more guidance on how pharaoh’s heart could be hardened while he retains his free will.
Steinem’s quote is talking about herself and her relationship with her mother, who was suffering from severe mental illness at the time. She says:
Perhaps the worst thing about suffering is that it finally hardens the hearts of those around it.
Which made me think of pharaoh. Could this simply be a part of the language barrier that exists between God, man and all the languages that are involved in getting us to where we can each understand the words in our separate texts? Could God have just been saying that the suffering of pharaoh’s people that God is about to inflict is just going to anger him instead of make him relent? Is God taking responsibility for upsetting pharaoh so much because an escalation of force is going to be necessary and He knows it?
The way Steinem speaks of her heart being hardened to her mother’s plight at the point in life she is speaking of reminded me that language and colloquialism are full of nuance and things could be just this simple. Though they could be far more complicated as well.