Imagine children playing on the beach, building sandcastles, they are giggling, enjoying their game when a big wave starts to close in. the children were not afraid, but rather they were very excited watching the waves wash away their beautiful creation. Even as little children, they knew the fate that awaits their creation, so they were not distressed or unhappy seeing it washed away into the sea.
The stuff of this world is about as permanent as sandcastles on a beach. Yet we get so caught up in it, defensive over it, and depressed over the loss of it. But God didn't create you for this world. Your destiny is not bound up in cash and bonds, land and houses, fame and monuments. So living to be a hundred years old is far less important than living well - Even if for a relatively short time. Beautifying your body is not nearly as urgent as living with a pure heart before God.
Children know that their castles in the sand are brief joys destined to be taken away by an incoming tide. So they don't fret as the waves approach. They typically watch their creations get swept away without shedding tears.
Everything about this life is so transient. The incoming wave of our mortality is going to sweep it all away. Like sandcastles at the edge of the ocean, nothing we do for the sake of this world can survive. Only what you do here for eternity will last. Only the treasures you send ahead will escape corruption.We are all vulnerable. We are all quite mortal. Everything about our existence here is about as enduring as sandcastles.