Benedictine monk, liturgist; b. April 7, 1908, Roscoe, Minn.; d. Feb. 22, 2002, Collegeville, Minn. The sixth of eight children of German emigrés from Westphalia, John Conrad and Rosalie (Loxterkamp) Diekmann, he was baptized Leo. After his education at St. John's Preparatory School and two years at St. John's University in Collegeville, Minn., he joined the Benedictine Order there in 1925. This was the same year that Virgil michel, just back from his European studies and thoroughly inspired by Lambert beauduin, began to promote an American liturgical movement. During Diekmann's first year in the abbey, Orate Fratres (later renamed Worship ) was founded and the Liturgical Press began publication of its Popular Liturgical Library. He also learned of the theology of the mystical body of christ, which was for him the discovery of a new ecclesiology with profound liturgical ramifications.
In 1928 Diekmann was sent to Rome to pursue a Doctorate in Sacred Theology at Sant' Anselmo. There Dom Anselm Stolz introduced him to the Church Fathers, particularly Tertullian, whose writings became the focus of his dissertation. Diekmann was ordained to the priesthood on June 28, 1931. He returned from Europe in 1933, and became a professor of theology at St. John's University, where he taught for 62 years. Also in 1933, he was appointed assistant editor of Orate Fratres. Upon Virgil Michel's sudden death in 1938, Diekmann succeeded him as editor and began soliciting regular contributions from a circle of young scholars including Hans Ansgar Reinhold, Kathryn Sullivan, Frederick McManus, and Gerard Sloyan.
Diekmann's association with the annual Liturgical Weeks secured his role as a key leader and spokesperson of the liturgical movement in the 1940s and 1950s. These Weeks were launched under the auspices of the Benedictines in 1940 and were sustained by the creation of the Liturgical Conference in 1943. His gift to the movement was to provide a vision of sacramental life solidly grounded in patristic sources and always oriented to the church's pastoral life.
By the 1950s Diekmann was a regular participant in study weeks and conferences in Europe. At Lugano (1953), Louvain (1954), Assisi (1956), and Monserrat (1958), he heard scholars and pastors together with representatives from the Sacred Congregation of Rites openly debate a wide range of pastoral liturgical reforms, including Holy Week reforms, readings in the vernacular, a three-or four-year cycle of Scripture readings, concelebration, vernacular recitation of the breviary, and restoration of the catechumenate. Diekmann was invited to serve as a consultant to the Pontifical Liturgical Preparatory Commission of the Second Vatican Council. His work on the commission included drafting the articles on the cultural adaptation of the liturgy (Sacrosanctum Concilium 37–40), articles that he judged, in retrospect, not nearly bold enough in promoting diversity of rite and adaptation to given cultural structures. He also lobbied for permission to recite the breviary in the vernacular.
Diekmann was nominated by Archbishop Paul Hallinan as a peritus to the council for its second, third, and fourth sessions. He was instrumental in the founding of the international commission on english in the lit urgy (ICEL), and served on its advisory committee from the beginning. With the close of the council, Diekmann became one of the most sought-after interpreters of its content and implications. His interest in ecumenism was manifest in his membership in the National Lutheran-Catholic Dialogue and his positions as founding fellow and professor at the Ecumenical Institute for Advanced Theological Studies at Tantur, Israel, and co-founder of the Ecumenical Institute of Spirituality.
He retired from teaching in 1995 and continued to reside at St. John's Abbey until his death on Feb. 22, 2002.
Bibliography: k. hughes, The Monk's Tale: A Biography of Godfrey Diekmann (Collegeville 1991); includes comprehensive bibliography of the works of Godfrey Diekmann, 345–365.