In April 1963, Bishop Harmon made civil rights history when he, along with seven other white clergymen (including fellow-Methodist Bishop Paul Hardin Jr.), released a statement calling on African Americans to stop taking part in demonstrations initiated by the Rev. Dr. Martin Luther King Jr.. The statement, titled "A Call for Unity," called the demonstrations "unwise and untimely," and argued that change should be pursued through negotiation and judicial action. This statement motivated Dr. King to write his famous "Letter from Birmingham Jail." In his 1983 autobiography, Bishop Harmon referred to the letter as a "propaganda move," but also wrote that he "certainly gave his due as a brave man fighting off ages of evil."