Too bad he wasn't able to just "read their hearts" and skip all the drama with the "fish.
He did, that is why he condemned them in the beginning.
This is an interesting conversation, and I believe it revolves around the age old question of free will.
If we truly are created in God's image, with his capacity to feel all the emotions he feels, why is it surprising then to read God being angry, happy or upset?
If we accept that God is greater than his creation, including us human beings, then we can understand that we are left with being able to interpret God's actions at best. As peacefulpete asked, is it a non retractable judgment, or is it a warning? I think arguments can be made for both.
However, if we cannot accept that God is greater than his creation, we'll attempt to bring him down to our convoluted and confused level.