The answer is: Psalm 90

Psalm 90 - This psalm, attributed to Moses, reflects on the brevity of human life and God’s eternal nature. It contrasts the fleeting existence of man with God’s everlasting presence. Interestingly, it serves as a lament but also calls for wisdom (90:12), paralleling themes found in Ecclesiastes regarding the meaning of life.

Psalm 90, “A Prayer of Moses”, is a profound meditation on human mortality and divine eternity. This psalm stands as only one of the few attributed to Moses, a towering figure in the biblical narrative. Unique in its voice, it offers us a glimpse into Moses’ life experiences — leading a people through wilderness years while grappling with their collective struggles.

Did you know that Psalm 90 is often regarded as the oldest psalm in the book of Psalms? It reflects an intrinsic wisdom about life that resonates through the ages. The line “teach us to number our days, that we may gain a heart of wisdom” (90:12) encourages a game-changing viewpoint that cherishes gratitude and mindfulness in our daily lives. Instead of being maudlin about our fleeting existence, it invites us to embrace life's transitory moments with intention.

Furthermore, you can trace echoes of Psalm 90 throughout the rest of scripture. Notably, the sentiments expressed here also appear in the book of Job — another text that wrestles with pain, meaning, and hope. It subtly reminds us that we’re like wildflowers, blooming briefly yet dramatically, teaching us the significance wrapped in our everyday moments rather than just the grand milestones. Reflecting on Moses' turmoil gives us a deeper appreciation of our purpose and circumstances, tethering ourselves in time while reaching for the divine. Isn’t it fascinating to see how one ancient prayer can resound throughout generations?