"The first theologian in modern times to discover to our wonder and joy the fully sacramental character of the Mass was, doubtless, that profound and personal thinker, Abbot Vonier." - Fr. W. Barden, O.P. In his greatest, and most influential masterpiece, Abbot Vonier gives a spiritually and intellectually enriching explanation of the Eucharist based on a careful study of "the great sacramental doctrine of the Church" found in the teachings of St. Thomas Aquinas and the Council of Trent. Vonier writes, "To conceive the sacrifice of Mass as a sacrament is a simple visualization of a great truth which, if it be once grasped by the mind ... makes all the difference between light and fantasy." The great beauty and intellectual clarity of the Church's theology as explained by Vonier reminds the reader over and over that "In theological matters the spark that illumines always comes from under the hoof of strict reasoning."