The outcry over the nomination of 20 white actors, and no black ones, for the Academy Awards gained momentum on Monday — Martin Luther King’s Birthday — as the director Spike Lee and the actress Jada Pinkett Smith announced they would not be attending the ceremony on Feb. 28.

But at a star-studded gathering of mostly black performers to honor Dr. King, organized at Riverside Church in Harlem, mentions of the Academy Awards were kept in check, even by those whose films and performances were ignored.

Neither the event’s host, Ryan Coogler, the director of “Creed,” nor the film’s stars, Michael B. Jordan, who read a Fred Hampton speech before a rapt crowd, and Tessa Thompson, who read one by Angela Davis, alluded to the complaints surrounding the nominations. (The only Oscar nomination for “Creed” went to Sylvester Stallone, for his performance as a supporting actor.)

Chris Rock, the comedian scheduled to host the awards, also kept on message after taking to the church’s stage following Mr. Jordan, reciting “My Dungeon Shook” by James Baldwin.