Nothing is more surprising than the passing of time.

People are always surprised at how quickly time flys by; and to the extent that 'time' almost seems unnatural. You look back at an old photo, and you can't believe that it was ten years ago.

I read a CS Lewis quote that said it's like a fish constantly being surprised by the wetness of water. The only possible reason for this constant, repetitive surprise is that it was never meant to be part of our existence. It's like a massive clue that we were created for eternity. We weren't meant to age, or have our bodies slowly ravaged by the toils of life.

"He has also set eternity in the hearts of men; yet they cannot fathom what God has done from beginning to end."
Ecclesiastes 3:11

I love this verse. In the first instance it states that we have this innate sense of eternity, and in the second it declares that we're simply unable to comprehend how the universe came into existence. Seems to have massive implications on theories like evolution and the big bang. It's simply beyond our intelligence to understand, no matter how factual we present our theories.