This is not me saying you’re wrong because I don’t think you are, but as a fun thought experiment, I know the argument for this from the theologist perspective. There’s quite a lot of philosophy behind it.

Being both omniscient and omnipotent simultaneously would require a totally different perspective of time. God would need to be an observer to all that is, was and will be at once as if you were looking at a painting. But to make changes to that painting, if you will, God would need to enter time to interact with the people of his creation to make things so.

You have this sort of chicken and egg situation as a result. While God theoretically knows Abraham is faithful, he knows Abraham is faithful through the trials of Abraham which God would have had to perform to know what he knows. So in effect, God knows the result of these actions before hand, but the actions still must occur, otherwise God would not know.

I don’t have time or the memory to drive deeper into this discussion but I remember this was a very long discussion I had during my theology studies before I left the church.