“Where people break down the dividing wall of hostility which separates them from their brothers, Christ achieves his ministry of reconciliation.” One speech, two locations and very different impacts.

The Rev. Martin Luther King Jr. spoke those words in front of more than 20,000 people in the West Berlin Waldbühne amphitheater on Sept. 13, 1964, and triggered nods of agreement. Christians in the audience understood it as a metaphor. Just months before, King had celebrated the enactment of America’s landmark Civil Rights Act of 1964, which banned discrimination.

Yet the same words repeated a few hours later in two overcrowded churches in East Berlin produced breathless silence. Because for many citizens of the German Democratic Republic, the “dividing wall” was no metaphor.

King had the opportunity to see this with his own eyes, when, in the early hours of Sept. 13, Michael Meyer, a 21-year-old jockey from the GDR, was shot while crossing the border but pulled over the wall to freedom by a U.S. soldier. King rushed to the scene, gave interviews and talked to the inhabitants of a West Berlin apartment block that had been hit by numerous bullets.

While King had been officially invited to West Berlin by Mayor Willy Brandt to join a memorial ceremony for U.S. President John F. Kennedy, the invitation to East Berlin was private, from Provost Heinrich Grüber. Grüber had joined the church resistance against the Nazis and was imprisoned in a concentration camp. But by 1964 he’d become a critic of the restrictive church politics of the GDR’s ruling party, the SED (Socialist Unity Party of Germany). He had been barred from visiting his parishes in the GDR since the erection of the wall in 1961. Perhaps Grüber sought a way to support his colleagues in East Berlin, some of whom had been driven to the west or arrested.

U.S. authorities had confiscated King’s passport in West Berlin, possibly out of concern for his safety or because they intended to deny him a popular event in the east. However, GDR border guards recognized the preacher and, after a quick phone call to superiors, allowed him to enter. King’s American Express card was all the identification he needed.

What he couldn’t have imagined at Checkpoint Charlie: The church (Marienkirche) in which he was to talk was overflowing an hour before he was supposed to arrive. This despite an SED order to newspapers not to mention the visit. Only a small board outside the church announced the event, and yet, around 3,000 GDR citizens showed up. The pleas of church leaders to the hundreds of people waiting to please leave fell upon deaf ears. After a short deliberation, they announced that King would hold a second speech in the nearby Sophienkirche.

While King’s criticism of the U.S. government and his fight against apartheid appealed to GDR leaders, King’s campaigns for peaceful mass protest did not.

King captured the audience with his first words. He delivered greetings to “dear Christian friends from East Berlin” from the Christians in the western part of the city and from the United States, and he thanked his parents, who had given him the name of the great German reformer Martin Luther.

“We, who felt trapped and abandoned, were sent greetings from Christians in the west. This really moved me,” remembers one member of the audience. King then talked about his beliefs, his philosophy of nonviolence and his vision, without commenting on recent events.

“Here are God’s children on both sides of the wall, and no man-made barrier can destroy this fact,” King shouted. “With this faith we will be able to tear out of the mountain of despair a stone of hope.” In faith, people can stand up for freedom “in the knowledge that one day we will be free.”

Of course, the SED regime needed to know what was going on in the church. Stasi spies joined and a photographer from the feared secret service took impressive pictures. In July 1964, GDR newspapers such as the Neues Deutschland had praised the “negro leader Dr. Martin Luther King” for denouncing the nomination of conservative Barry Goldwater for U.S. president. But the GDR press published only dry reports on the speech that day and failed to mention King’s words about barriers and walls. There was a halfhearted attempt to portray King as a labor leader.

Stefan Appelius, political scientist and professor of contemporary history from the University of Oldenburg, says that while King’s criticism of the U.S. government and his fight against apartheid appealed to GDR leaders, King’s campaigns for peaceful mass protest did not. “This was something to which the GDR leaders could not really relate,” he said.

Martin Luther King’s visit to East Berlin came to an end in the restaurant of the Hospiz an der Friedrichstraße. The Hotel Albrechtshof stands there today, and a plaque bears a reminder of the visit. Photos from the meal show the American minister at the table in enthusiastic discussions with the East Berlin pastors as they enjoyed beer, wine and fat cigars.

The visit had a lasting effect. “His call to have courage, to resist peacefully … gave many people the strength to protest against the crushing of the ‘Prague Spring’ — the uprising against Communist rule in Czechoslovakia — four years later,” says Appelius.