What examples of figurative language can be found in Martin Luther King Jr's "I Have a Dream"?

In addition
to the metaphors noted in other answers, King repeatedly relies on a variety of figurative
language devices, giving his speech a deeply poetic cadence.

For example, he
uses repetition freely, especially in the form of , where the
beginning words of a line are repeated over and over to create a rhythmic effect. This
repetition also helps us to remember what was said. Some examples of anaphora in King's speech
are as follows: "Now is" is used to begin a group of statements in paragraph nine,
while "we can never be satisfied" begins a series of short paragraphs starting with
paragraph 14, and, most famously, King uses many, many repetitions of the words "I have a
dream."

King also uses , which is the
juxtaposition of opposites. For example, he refers to President Lincoln's Emancipation
proclamation as:

a joyous daybreak to end the long night
of captivity.

Daybreak is the antithesis of long
night.

He also states that his movement hopes to:

transform the jangling...