MLK, Jr. in the early 1960s. (Getty)
On February 10th, 1963 Dr. Martin Luther King Jr. delivered a speech at the historic Plymouth Church in Brooklyn Heights—it was called “The American Dream,” and echoes of it were heard in his “I Have a Dream” speech later that year. He began, as he often did while at speaking engagements like that one, by thanking those in front of him:
I need not pause to say how very delighted I am to have the privilege of standing in this historic spot, this sacred spot, the opportunity of being in this church so rich in history and with such a rich tradition. It is always a deep and rewarding experience when I can take a brief break from the day-to-day demands of our struggle for freedom and human dignity in the south, and discuss issues involved in that struggle with people of good will over this nation. And so I say I'm delighted to be here, and I am deeply grateful...
The church (which Abraham Lincoln attended twice) was founded in 1847, and is believed to have been a part of the Underground Railroad. That, and its history of advocating for human rights, prompted King to accept their invite on that date, which was the day the church became a National Historic Landmark.
The church's director of history ministry services, Lois Rosebrooks, who recently retired, was there the day MLK, Jr. took over preaching duties, as part of the choir. She recalled it being “jampacked" that day. Here's the speech, which he also delivered elsewhere around that time.
The full speech can be read here.