Lord! Whose love in [and] power excelling. Bishop R. Heber. [Epiphany.] Appeared in his posthumous Hymns, &c., 1827, p. 35, in 4 stanzas of 4 lines. It is based on a part of the Gospel for the 3rd Sunday after the Epiphany (the healing of the Leper). It is in common use in Great Britain and America, and usually without alteration.
--John Julian, Dictionary of Hymnology (1907)