In Cormac McCarthy's novel "The Crossing," the author reflects on the transient nature of human endeavors and the inevitable passage of time. The quote, "The passing of armies and the passing of sands in the desert are one," highlights the idea that both monumental military movements and the shifting sands of the desert symbolize the impermanence of existence. This suggests that no matter how grand or powerful, all things eventually fade away.

McCarthy draws a parallel between the relentless march of history and the natural world, emphasizing that both are subject to change and erosion. Armies may conflict and strive for dominance, but ultimately, like the sands, they too will dissolve into memory. This profound observation invites readers to reflect on the futility of human ambitions against the backdrop of an ever-changing universe.