And when this happens, and when we allow freedom ring, when we let it ring from every village and every hamlet, from every state and every city, we will be able to speed up that day when all of God's children, black men and white men, Jews and Gentiles, Protestants and Catholics, will be able to join hands and sing in the words of the old Negro spiritual: "Free at last! Free at last! Thank God Almighty, we are free at last!" (21.1)

This is the type of thing you would hear being sung in an African American Baptist church. Like a post-service hymnal, the song is meant to leave people with a feeling of hope and warmth as they exit. Think of the way you felt at the end of The Shawshank Redemption …and then multiply it by a thousand and apply it to real life.

This closing line is also a masterful example of oratorical flow, which is kind of like rap flow, except without a sick beat. It's an entire paragraph consisting of just one elegant sentence. The single sentence mirrors the idea of a unified society—different groups getting along, as one. It also keeps the audience waiting, hanging on every word, until the big climax: free at last. To mix musical metaphors, this is sort of like how house music has huge bass drops after a build-up.

Along with all this, the closing sentence crystallizes the universality of King's vision. His dream is not just to promote the rights of African American people. It's applicable to everyone—all Jews, and Catholics, Protestants and Gentiles. Ending on this note is a call to urgent action for people beyond the African American community.

Seriously: go take a listen to the speech. We promise: you'll feel elated and revved up to go out and effect some dang change in the world.