What elements of a sermon do you notice in King's speech?
The techniques of a sermon are present in Dr. King's oratory, in general. Like most effective sermons, Dr. King maintains a strong rapport with his audience. Throughout the speech, one notices that he is speaking with them and not at them. He is able to work through and integrate their applause, and sounds of affirmation throughout. He does not create an atmosphere of tension and discord through his words, but rather establishes an environment of community. This helps to firmly embed the idea that God is on his side, on their side. Due to this, another sermon technique that is evident is his command of the audience which he establishes at the start and drives through the very end of the speech/ sermon.
"I Have a Dream" was originally a speech, not an essay in a book; therefore it is a direct address and it contains many similarities to a sermon: many images, much repetition, proximity to a greater voice, and parallelism. The proximity to Lincoln, of course, is partly responsible for the opening words: "Five score" echoes Lincoln’s "Four score and seven years ago." The imagery ranges from the commercial imagery of the check that is being belatedly cashed (entirely appropriate if only because blacks have indeed been kept out of the better-paying jobs), to biblical imagery (for instance, the searing flames, the rock, the cup of bitterness, and the reference to Negro spirituals), to patriotic imagery ("My country, ’tis of thee"), but of course the ostensible framework is a dream-vision of a free (and therefore happy) society. King calls only for justice, but the point is that if justice rules, blacks and whites will at last be able to engage in "the pursuit of happiness."