Most prominent to me is the clear statement that, no matter how worldly-powerful you are, you are nothing when God comes against you. We see Egypt's massive splendor assailed by tiny Moses, and we know which was the victor.
Second, and requiring careful inspection, surely Martin has featured a cross in the dead-center distance, as well it was then.
Well, yes, I agree, but mostly because I used to go upstairs to the gallery and gaze upon the original painting 3 days a week after Art Class. I remembered it from the first time I went to the Museum when I was about 8 years old. It seemed to jump off the wall at me!
The whole Museum is awesome, but when I was a little kid all I remembered were the mummies and THAT painting.
Who would have thought that 60 years later I would be posting it on FR! :-)