Martin Luther King Jr. called on white church leaders to address racism. His "Letter from Birmingham Jail" has elicited a response from an ecumenical network. In the letter, King expressed his dissatisfaction with white moderates who "see my peaceful efforts as those of an extreme." He said they were wrong to see him as an extremist because black Americans needed to be mobilized in order to achieve racial equality. King argued that such people were not being completely honest with themselves or me. He said they could not see his efforts as nonviolent because violence was always necessary for change. Black Americans had been forced to use violence when other methods have failed, so it was not surprising that many white moderates rejected his plea for nonviolence. In addition to writing letters to King, several white clergy members met with him in person to discuss their concerns. One of these men was Ralph Abernathy, who later became King's chief of staff. Abernathy recalled that King was thoughtful and polite during their meeting, but he also said that King was firm in his belief that whites should abandon their comfortable lives and become involved in the civil rights movement. Abernathy remembered King saying that nonviolence required "a complete sacrifice of one's self," and he added that many blacks felt that white Christians were trying to get rid of King by removing him from the city jail.