Be thou ready, fellow mortal. [Readiness for Duty.] Appeared anonymously in the Unitarian Hymns for the Sanctuary, Boston, 1849, No. 609. These Hymns, &c, were edited by the Rev. C. A. Bartol and others, and are known as Bartol’s Collection. This hymn passed from that Collection into the Supplement to Hedge & Huntington's Hymns of the Church of Christ, Boston, 1853, and again into other hymn-books.
-- John Julian, Dictionary of Hymnology (1907)
Henry Wilder Foote notes in the DNAH Archives that this hymn's "theme and mode of expression suggest that it may have been written by [Cyrus Augustus] Bartol."