About Us

Our Story

Most Holy Trinity Seminary was founded in 1995 in a building which it shared with Mary Help of Christians Academy in Warren, Michigan. Since it was necessary that the seminary function in its own quarters, Most Holy Trinity Seminary acquired 50 acres of land in 2003 near Brooksville, Florida, (about 50 minutes north of Tampa) with a view towards constructing a new building and relocating its operations there. Construction began in April 2005. In April of 2008, the Seminary officially opened its doors in the new facility.

The Building

Our Approach

Most Holy Trinity Seminary was founded in order to provide priestly training for young men who thoroughly reject Vatican II, its reforms, and the Modernist hierarchy which promulgates them. This position is in contrast to the seminaries of traditionalist groups that operate with the approval of the Modernist hierarchy, or who seek this approval.

The Seminary trains priests according to pre-Vatican II standards. Its rule, discipline, spiritual formation, and academic curriculum imitate faithfully those which were in effect in seminaries before the Second Vatican Council. By training priests in this manner, the seminary hopes to contribute to the solution to the problem of the nearly universal disintegration of Catholic faith, morals, discipline, and liturgy  which the Second Vatican Council has caused.

The seminary sees that the only solution to the problem of Vatican II, however, is to condemn it as a false council which was dominated by heretics, and to discard and ignore its decrees and enactments. Consequently, the Seminary does not seek to be recognized by the heretical hierarchy which promulgates Vatican II, nor does it seek to work with the Novus Ordo clergy, as if in a single church or religion.

The Seminary therefore repudiates the idea of the Motu Proprio Mass, or that of a fraternity of priests which has received permission or seeks permission from the Novus Ordo hierarchy to function in communion with the Modernist heretics.

The Catholic Church, in the outlook of the Seminary, will not be cured of its current problems until the hierarchical sees, particularly the papacy, are once again occupied by Catholics. For as long as Modernist heretics possess the mere appearance of authority which they now possess, the problem of Vatican II will continue. In the meantime the Seminary, as well as the priests who emanate from it, shall abhor even the suggestion of an official recognition from the Novus Ordo hierarchy, or of a compromise with the Modernists, whom St. Pius X called the “most pernicious of all the enemies of the Church,” who are striving “utterly to subvert the very Kingdom of Christ.”


Our Seminary provides future priests with a thorough intellectual training based on the Church’s Magisterium and the Teachings of St. Thomas Aquinas. In both philosophy and theology it insists on adherence to classical Thomism.


Most Rev. Donald J. Sanborn

Founder & Rector

Bishop Sanborn is currently Rector of the seminary in Brooksville, Florida. He also travels frequently to Mass centers in the United States, and makes occasional visits to Europe, where he meets with both clergy and lay people who share or who are interested in his uncompromising position with regard to the Novus Ordo religion.


Most Rev. Joseph S. Selway

Vice Rector

Bishop Selway was consecrated by the Most Reverend Donald Sanborn in 2018, on February 22, the Feast of Saint Peter’s Chair at Antioch. He is presently the vice-rector of Most Holy Trinity Seminary, assists the parish and teaches Philosophy at the Seminary. He is also in charge of Queen of All Saints Academy.

Fr. D. (1 of 1)

Rev. Nicolás E. Despósito

Vice Rector

Father Despósito is originally from Argentina. He arrived at Most Holy Trinity Seminary in 2001. After his ordination in 2006, he stayed at the Seminary as a Professor. He currently teaches Dogmatic and Moral Theology.


Most Rev. Germán Fliess


Also from Argentina, Fr. Fliess was admitted as a seminarian in 2006. He was ordained in 2010 and after the completion of his studies in 2011, he became a professor. He currently teaches Dogmatic Theology, Sacred Scripture, Latin and Greek. He was consecrated a bishop in 2022.


Rev. Luke Petrizzi


Father Luke Petrizzi is from Virginia and was ordained in 2020. He currently teaches Church History and Latin. He oversees the Ceremonies and plays the organ.