It's what the clay does in response to the work of the Potter that matters.
Clay that does not conform will be made hard or soft entirely at the discretion of Potter.
“I will have mercy on whom I have mercy,
and I will have compassion on whom I have compassion.” - Romans 9:14
In his rebellion Pharaoh was hardened to destruction.
In his rebellion Paul was softened to glory.
Had Paul been like Pharaoh he too would have been hardened in his rebellion.
Its what the Potter does the living one. His understanding .Not the understanding of the work he forming Christ in .
In his rebellion the Pharaoh's natural heart was hard before it was challenged . We are given a new spirit and heart. One that can be softened. One not dead. Again no spirit life, heartless.
Spiritless, corrupted rudiments don't offer resistance. Only God can soften the clay and create new rudiments. Flesh and blood will not be part of the new. I no rebuilds or reconditioned in the new heavens and earth. the old the former things will not come to mind or be remembered forever more.
We have no part in the softening process. because it is Christ who does work in us to to both will and do His good pleasure .We should do so without murmuring . Without Christ we can do nothing .
Neither have I gone back from the commandment of his lips; I have esteemed the words of his mouth more than my necessary food. But he is in one mind, and who can turn him? and what his soul desireth, even that he doeth For he performeth the thing that is appointed for me: and many such things are with him. Therefore am I troubled at his presence: when I consider, I am afraid of him. For God maketh my heart soft, and the Almighty troubleth me: Because I was not cut off before the darkness, neither hath he covered the darkness from my face.Job 23:12-17
Ezekiel 11:19 And I will give them one heart, and I will put a new spirit within you; and I will take the stony heart out of their flesh, and will give them an heart of flesh: