Fr. Wilfred Robert Theisen OSB

Monk of Saint John's Abbey
Collegeville, Minnesota

Born: September 5, 1929

Professed: July 11, 1953

Ordained: 1956

Died: December 3, 2024

Robert John Theisen was the sixth of nine children born to John Franklin and Elizabeth Theresa (Tabery) in Wadena, Minnesota, on September 5, 1929.  At the age of four Robert lost his father whose death left his widowed mother with nine children, seven boys and two girls, all under the age of ten!

As was often the case in those years, the Benedictine Sisters, even at a boy’s early age, planted the seed of a vocation to the priesthood in Robert who was a model Mass server.  Consequently, he followed his brother, Eugene, to Saint John’s Preparatory School in 1943.  His declared vocation covered all the costs. As a student, Robert was inspired to want to pursue Benedictine monastic life by the generosity and kindness of the monks.  “Father Burton Bloms’ cheerfulness made it an attractive vocation for me.”

Following graduation as valedictorian in 1947 Robert was accepted that year as a freshman at Saint John’s University on a pre-divinity scholarship.  Two years later, he entered the novitiate. Robert’s cousin, then Prior Baldwin Dworschak, asked Abbot Alcuin to give him the name Wilfred, Baldwin’s own baptismal name, and professed simple vows as a Benedictine monk in 1950 and final profession in 1953. After completing divinity studies at Saint John’s Seminary he was ordained to the priesthood in 1956.

Father Wilfred’s education continued with summer graduate work at the University of Colorado, Boulder, where he earned an M.S. degree in physics in 1962. He then enrolled in a doctoral program at the University of Wisconsin, Madison, in 1966 and was awarded a PhD in the history of science in 1972.

Father Wilfred’s teaching career began in the physics department at Saint John’s University shortly after his solemn profession in 1953. He resumed teaching again in 1962, followed by another thirty-five years in the classroom from 1970–2005. At the end of his teaching career, Father Wilfred was duly awarded the title of Professor Emeritus of Physics by the SJU faculty. He was also a prefect in the university dorms during the decade 1956 through 1966 and then again from 1970–73. He recounts: “When I was a college faculty resident in the dorms for 12 years, I enjoyed the special relationships that bound that beleaguered group together.”

Father Wilfred became the liaison officer for the Collegeville Institute for Ecumenical and Cultural Research in 1975, a position he relished for forty years because of its intellectual stimulation. He was a perfect fit for this role because of his ability to translate monastic and Catholic spirituality to people of all faith traditions.  In addition, he worked as assistant director of Hill Monastic Manuscript Library at Saint John’s University (HMML) from 1978 through 1983. 

Father Wilfred was part of the chaplaincy team that ministered to the Sisters of Saint Benedict’s Monastery, Saint Joseph, Minnesota, from 1982–85, and then again in the years 1991 and 1992. Later, he volunteered as a receptionist at the Information Center in the Great Hall at Saint John’s University (2009–10).  He also found his volunteering for many years in the Abbey Gift shop a rewarding opportunity to meet and visit with alumni and other guests.

Father Wilfred punctuated his teaching career with two sabbaticals: one in Cambridge, England, in 1973–74; and another in Oxford, England, in the spring of 1986. His academic acumen was further reflected in National Science Foundation (NSF) Summer Fellowships at the University of Chicago and Argonne Laboratory and a National Endowment for the Humanities (NEH) Summer Fellowship at Harvard University. One of his favorite areas of research was the history of medieval alchemy.

As a homilist, Father Wilfred’s sermons were pithy and spot-on, frequently centering around points of ecclesiastical controversy. They were clearly meant to stimulate thoughtful discussion among the faithful. He loved to delve into the relationship between religion and science. He had a special interest in the reaction of the Catholic Church to the theory of evolution put forth by Charles Darwin. He publicly expounded his thoughts on this issue with colleagues in the university and at an Abbey presentation in January 2010.

For a number of summers, as a passionate golfer, Father Wilfred was stationed at a church on the edge of a golf course for weekly and daily Eucharist, at which he would have a regular discussion of Scripture and issues related to science and faith.  This assignment integrated a number of his skills!

Father Wilfred was passionate about his support of Johnnie athletics, perhaps especially football and basketball, and he loved to wax eloquently about the latest scores whenever he sensed a sympathetic confrere or a captive audience.  As a hobby, Father Wilfred enjoyed especially golfing, attending University sports games, and he busied himself with editing the alchemical works of John Dastin.

Father Wilfred clearly loved people and stayed connected with many alumni and friends.  He was welcoming of everyone and never overlooked an opportunity to extend hospitality to young and old with a friendly smile and engaging conversation.

Father Wilfred died on December 3, 2024, in the retirement center at Saint John’s Abbey. He is survived by his sister-in-law, Marilyn (Lyle), and the community of Saint John’s Abbey. The monks, family, and friends will receive the body at 7:00 pm on Thursday, December 5, and celebrate the Mass of Christian Burial for Father Wilfred at 9:00 am on Friday, December 6, in the Saint John’s Abbey and University Church, with interment in the Abbey Cemetery. The service may be viewed on YouTube.