Some words, songs and books stop being ordinary things and become something much bigger. That is the simple idea running through "There is." The speaker lists moments when a poem, a song, a book or even a single phrase turns into more than what it first seemed. The repeated opening, "There is a time... There is a day... There is a place," gives the poem a steady, almost chant-like rhythm, as if the speaker is counting off examples of something that happens to everyone.
The second half moves from the general to the personal. Once something "burries deep" in your mind, even a brief mention or a glimpse can set off "thousands of memories, feelings" that rush back into the present. The word "spiraling" suggests how they swirl and can't be controlled. The final line says this feeling can never be erased.
The mood is reflective and quietly tender. It could be nostalgic, but the poem doesn't say whether these memories are happy or painful, and that openness is part of what makes it relatable.