Spirit of Truth! on this Thy day. Bishop B. Heber. [Whitsuntide.] Appeared in his posthumous Hymns, &c, 1827, p. 82, in 6 stanzas of 4 lines. It is in several modern hymnbooks in Great Britain and America, and usually in an abbreviated form. For the date 1812, sometimes assigned to it, we have no evidence.
-- John Julian, Dictionary of Hymnology (1907)