Speech by Martin Luther King, Jr. against the “triple evils of racism, economic exploitation, and militarism.” Audio.
This speech was released by Black Forum records, a subsidiary of Motown, and went on to win a Grammy (in 1972, according to Wikipedia, in 1970, according to Grammy website) for the Best Spoken Word Recording.
Excerpts of a Sermon at the Ebenezer Baptist Church on April 30, 1967.