Prune thou thy words, thy thoughts control. Cardinal Newman. (Flowers without Fruit.) “Written off Sardinia, June 20, 1833." It was published in Lyra Apostolica, 1836, p. 80 (ed. 1879, p. 85), in 3 stanzas of 8 lines.
--John Julian, Dictionary of Hymnology, Appendix, Part II (1907)