John Lewis on Martin Luther King Jr.'s Greatest Gift to Us

The following feature is excerpted from LIFE Martin Luther King Jr.: 50 Years Later, available at retailers now

I was 15 the first time I heard Reverend Martin Luther King Jr. preach. He was the pastor of the Dexter Avenue Baptist Church in Montgomery, Ala., leading the city’s bus boycott, and his weekly sermons were carried on the radio. This particular sermon was called “Paul’s Letter to American Christians.