I'm no MLK scholar but I'm intrigued by his final speech given on April 3rd, 1968 in Memphis, Tennessee. Dr. King was there in support of black garbage collectors who were on strike for better wages. It's almost like he knew his life was in jeopardy and he was preparing himself for the afterlife. You can read a transcript of the entire speech here. I've pasted in the final paragraph.
Well, I don't know what will happen now. We've got some difficult days ahead. But it really doesn't matter with me now. Because I've been to the mountaintop. [applause] And I don't mind. Like anybody, I would like to live a long life. Longevity has its place. But I'm not concerned about that now. I just want to do God's will. And He's allowed me to go up to the mountain. And I've looked over. And I've seen the promised land. I may not get there with you. But I want you to know tonight, that we, as a people, will get to the promised land! So I'm happy, tonight. I'm not worried about anything. I'm not fearing any man. Mine eyes have seen the glory of the coming of the Lord!