At the head of the Thomas Aquinas College’s academic quadrangle stands its most beautiful — and important — structure, Our Lady of the Most Holy Trinity Chapel.
Designed by University of Notre Dame architect Duncan Stroik, in collaboration with late Thomas Aquinas College president Thomas E. Dillon,  Our Lady of the Most Holy Trinity Chapel is, like the College’s classical curriculum, drawn from the greatest sources of the Western tradition. The building’s dome is representative of the College’s fidelity to Rome; its bell tower evokes California’s Mission history. Together, they announce the essential role of the Catholic faith in the life of the College.
From the College’s earliest days, officials hoped to build a glorious house of worship on campus, one worthy of the building’s sacred purpose. Those plans were long deferred, however, due to financial limitations and the urgency to establish basic campus needs such as classrooms, dining facilities, and residence halls. Thus, for most of the College’s first four decades, its liturgical life was confined to a small, modest chapel housed in the Commons building.
Only in the mid-1990s, under the devoted leadership of President Dillon and with a lead gift from the Dan Murphy Foundation, was the College able to pursue in earnest the creation of a permanent chapel. After a dozen years of planning, thousands of contributions from generous benefactors, and more than three years of construction, Our Lady of the Most Holy Trinity Chapel was dedicated on March 7, 2009.
Adorned with original statues, sacred artwork, and Biblical inscriptions, the Chapel itself is, as Dr. Dillon intended, a church that teaches . Its cruciform shape, like the golden crucifix atop its Bernini-inspired baldacchino, is a reminder of the Sacrifice that takes place during every Mass. Its seven arches symbolize the seven sacraments, the seven gifts of the Holy Spirit, the seven dolors of the Blessed Mother, her seven joys, and the three theological and four natural virtues. Through its every detail and its very design, which has garnered widespread acclaim , the building invites visitors to contemplate the greatest truths of the Faith.
The Chapel is named for Our Lady, our model in all human endeavors because of her unique relationship with the Persons of the Most Holy Trinity, the study of which is the culmination of students’ work at the College. And as the Universal Church is identified by Four Marks — one, holy, catholic, and apostolic — so is the Chapel. Those marks are beauty, which disposes us to what is true and good; grandeur, which lifts the mind to contemplate God’s transcendence; permanence, which signifies that God’s word is everlasting; and tradition, which connects us to the wisdom of the past.
Our Lady of the Most Holy Trinity Chapel is a fount of grace for the students, the faculty, the staff, and the friends of Thomas Aquinas College. Here, faith is nurtured. Here, conversions, baptisms, and confirmations take place; sins are forgiven; souls are nourished with Christ’s Precious Body and Blood. Here, young men and women discern their vocations and dedicate their lives to the service of Christ and His Church. Some hear the call to the religious life or the priesthood . Others answer the call to marriage, and some stand before the Chapel’s marble altar to be united in the Sacrament of Holy Matrimony.
Entering the Chapel through its barrel-vaulted loggia, an inscription reminds us, through the words Jacob uttered upon awaking from his heavenly dream, of the reason one comes to a church: “This is a house of God and gate of heaven” (Gen. 28:17). And exiting the Chapel through its bronze doors, another inscription reminds us, through the Blessed Mother’s advice to the wedding servers in Cana, of our foremost duty upon leaving: “Do whatever He tells you” (John 2:5).