Very few in the history of the church have not struggled with the dogma of the Trinity. Those who have not dismissed it as incomprehensible gibberish have found it a battlefield for division and misunderstanding. Even Christians, who adhere to the faith of the Creeds, have often found such dogma difficult to grasp. Richard of Saint Victor, a twelfth-century Scottish monk and Prior in the Abbey of Saint Victor, is emblematic in this struggle: ""I have often read that there is . . . [only] one God . . . I have also read . . . that he is one and triune . . . But I do not remember having read anything on the evidences for these assertions."" Richard's theological response stems from a profoundly mystical life of prayer, which, in the Spirit, seeks to involve the mind, in continuation with the great Augustinian and Anselmian tradition. Ultimately, he presents a trinitarian model, intelligible to a Western context but which could also awake admiration from Greek theologians. Today Richard's dogmatics could represent a bridge for dialogue between different traditions. For the first time this theological masterpiece is being made available, unabridged, in English to allow a broader theological public to benefit from Richard's accomplishments. The translation offered here attempts to provide a clear and flowing text, while remaining as literally faithful as possible to the original Latin. ""This first English translation of Richard of St. Victor's De Trinitate is a notable publishing event. Ruben Angelici's helpful introduction is both lively and learned. It is to be hoped that this project will renew the interest of theologians and philosophers in the stimulating theology of Richard of St. Victor."" --Paul Helm Teaching Fellow Regent College, Vancouver ""Ruben Angelici deserves great credit for his commentary and translation of Richard of St. Victor's On the Trinity. His scholarship is impeccable and insightful and his translation is accurate and lucid. This is a most welcome and much needed contribution to the theological academy."" --Thomas Weinandy, O.F.M. Executive Director of the Secretariat for Doctrine United States Conference of Catholic Bishops Ruben Angelici is a Graduate of the University of Manchester. He holds degrees and expertise in theology, philosophy, biology, and music. He has been a sessional lecturer in dogmatic and historical theology at Nazarene Theological College, University of Manchester.