Your harps, ye trembling saints. A. M. Toplady. [Encouragement to Believers.] Printed in the Gospel Magazine, Feb. 1772, in 8 stanzas of 8 lines, and headed "Weak Believers Encouraged." It was included in his Hymns on Sacred Subjects, &c, London, W. H. Collingridge, 1856; and in D. Sedgwick's edition of his Hymns and Sacred Poems, 1860. Several abbreviated forms of the text, all beginning with the original first line, are in common use in Great Britain and America. There is also in American use a cento beginning "If through unruffled seas," in 4 stanzas of 4 lines, of which stanzas ii.-iv. are from this hymn, and stanza i. is by another hand. It is given in the Songs for the Sanctuary, 1865, the Laudes Domini, 1884, and others.
--John Julian, Dictionary of Hymnology (1907)