TobyMac, Michael Tait (lead singer of the Newsboys), and Kevin Max were part of a Christian group called dcTalk that began in the late '80s. They wrote a song called Free At Last that was a tribute to Martin Luther King, Jr.
In 1992, they were invited to perform the song on the Arsenio Hall Show to celebrate Martin Luther King, Jr., Day. We'll do the math for you - that was 24 years ago.
Free at last, free at last, I thank God I'm free at last!