I
Campion said: “He’s God. He can do whatever he wants. “
Psalm 115:3 says, "Whatever he wills to do he does."
I think it is clear that if he does it, he can do it.
Therefore the verse from Psalm 115:3 implies:
Whatever he wills to do he can do.
I cannot see the difference between "whatever he wills to do he can do, and "He can do whatever he wants."
IIa
When asked to defend the proposition that God can NOT do whatever he wants, you adduce a text which says God cannot lie.
That could only be a refutation if it were agreed that God wants to lie. Otherwise you have only shown that there are some things God does not want to do and cannot do. You have NOT shown that it is not true that he can do whatever he wants.
IIb
Do you not think lying is evil? If you do think lying is evil, AND you think the text showing that he cannot lie refutes Campion, THEN can we conclude that you think God might or could want to do evil?
IF so, THEN either God is not free OR freedom can include wanting evil.
The first is interesting. The second is precisely the kind of thinking you say Protestants do not do.
So do you think God is not free? OR Do you agree that God can indeed to whatever he wants?
The “He’s God. He can do whatever he wants. “ is generally the false premise used by atheist in thinking that they are posing some kind of clever argument against God.
It is not true, therefore ANY argument for or against God using that premise is useless and a waste of breath.
If you're going to debate something, at least start with something that can even be remotely considered true.