The Lectures on Faith, important since 1834 to the theology of The Church of Jesus Christ of Latter-day Saints, are of disputed authorship. In an attempt to ascribe the lectures to their true author from five possible candidates, Joseph Smith, Sidney Rigdon, Parley P. Pratt, Oliver Cowdery, and W. W. Phelps, the use of 738 function and other words in the lectures was compared with the use of the same words in known writings of the candidates.The study showed that Sidney Rigdon's use of function words corresponded very closely with that in Lectures One and Seven, and fairly well with Two, Three, Four, and Six. Joseph Smith's use of function words matched closely those in Lecture Five, with some evidence of his having co-authored or edited Two, Three, Four, and Six.