“It is true that the negro race is barred from holding the Priesthood, and this has always been the case. The Prophet Joseph Smith taught this doctrine, and it was made known to him, although we know of no such statement in any revelation in the Doctrine and Covenants, Book of Mormon, or the Bible.”
Joseph Fielding Smith, The Improvement Era – Vol. 27, No. 6 (Salt Lake City, UT: The Church of Jesus Christ of Latter-day Saints, April 1924), 565.