Francis Grimke (1850-1937), the son of a white plantation owner and a slave, was the pastor of 15th Street Presbyterian Church in Washington, D. C., from 1878 until 1928 (with a brief pastorate in Jacksonville, Florida, in the middle of that period). He left his Charleston, South Carolina, home after the Civil War, and attended Lincoln University in Pennsylvania. From there he went to Princeton University, graduating in 1878. He was an ardent advocate for the rights of African-Americans, and helped to found the NAACP in 1909. His ministry was not only one of preaching, but of writing as well, and his collected writings are contained in the four volumes found here.
Here's a sample of what Grimke had to say on preaching: "In preaching are we seeking to impress the truth, or to impress ourselves upon others,—to draw men's attention to Jesus Christ or to ourselves? Too often it is of ourselves that we are thinking; and this is one reason why, though we may preach brilliant and eloquent sermons, they are attended with so little results in the development of Christian character, in the building up of those who listen in faith and holiness. The preacher's aims should be to get such a clear conception of the truth, and should be so impressed with its value, its importance, that in his effort to present it, he will not only lose sight of himself, but his hearers also will, in thought of the truth. It is of no importance whatever that our hearers should think of us, but it is important that they should
think of the truth of God presented." (Volume 3, page 3)