Music

Music symbolizes divine creation. The speaker expresses a belief that, in Heaven, he will become God's "music" (3). This symbolizes a sense of the abstract but artistic power of creation.

Maps

Maps represent the human attempt at understanding. The speaker compares his body to a map, where his physicians are searching for an answer to his illness. However, the speaker is aware of the imperfection of a map's attempts at representing reality, as it creates a sense of division where things ought to be connected.

Straits

Straits symbolize difficulty. This is a pun – a "strait" is a narrow body of water between two landmasses, but it has also come to mean "a difficult situation." Donne uses the word, in both senses, throughout the poem.

Purple

Purple represents royalty. The color purple was reserved for the use of Emperor in ancient Rome, and never lost its association with...