O God, the Rock of Ages. Bishop E. H. Bickersteth. [Sunday after Christmas.] In his note to this hymn in his annotated edition of his Hymnal Companion, 1880, Bishop Bickersteth says that "this hymn was written by the Editor (1860),"but in his work. The Two Brothers, &c, 1871, p. 226, it is dated "1862." It was included in the English Presbyterian Psalms & Hymns, 1867; the Hymnal Companion, 1870 and 1876; and the author's From Year to Year, 1883. Its use has extended to America and other English-speaking countries.
--John Julian, Dictionary of Hymnology (1907)