The Tides

With a title like "The Tide Rises, the Tide Falls" we've definitely gotta talk about the tides, right? First and foremost, they symbolize a natural world that is ever-lasting. Unlike the traveler, who very clearly dies, the tides keep on going. This the speaker's way of saying that nature itself—the physical world that we all know—is permanent, human life only temporary. We're all gonna die, that's a fact, but those tides (and the world they symbolize), well, they'll just keep on keeping on.

• Line 1: The phrase that will serve as the poem's refrain makes its first appearance. The rising and falling of the tide symbolizes life and death, and the cycles of nature more generally.
• Line 5: The first line of the poem is repeated here, and is now a true refrain. The inclusion of "and" is important, as it reminds us that the rising and falling of the tide is something that happens over and over and over and over. 
• Line 10: The refrain comes after a description of the effacement (erasure) of the traveler's footprints. The effacement of the footprints symbolizes the traveler's death, while the refrain suggests that his death is part of a larger natural cycle symbolized by the tides.
• Line 15: The poem ends where it began—with a line about the rising and falling of the tides. As a result, the poem's theme that life is characterized by a series of cycles is emphasized (the poem itself is a mini cycle).