The same idea is expressed by the Rebbe, Reb Bunim of Peshischa on the possuk "הִנֵּה טְפִחוֹת נָתִּתָּה יָמָי," You have made my life just handbreadths long (תהלים לט ו). He says that this possuk imparts a profound lesson on how we ought to perceive life. Our lives here on earth are analogous to a long rope. Even when holding a long rope, one has only one hand's breadth in their grasp at a time, while the rest of the rope's length lies either before or after their hand. Similarly, we should not view life as a long, endless stretch, but rather focus on the fleeting moment at hand and endeavour to make the most of it. We must realise that we cannot control the past or the future, so we should not worry about them or, for that matter, depend on them. Just like the length of the rope, they are not in our "hands".
This possuk encourages us to live in the present and appreciate each instant, no matter how small or seemingly insignificant it seems. It reminds us that every moment in life is precious, and we should make the most of every opportunity that comes our way.