TUMI is committed to retrieving the Great Tradition for the revitalization and enrichment of the urban church. The Great Tradition represents that evangelical, apostolic, and catholic core of Christian faith and practice which came largely to fruition from 100-500 C.E. Its rich legacy and treasures represent the Church’s confession of what the Church has always believed, the worship that the ancient, undivided Church celebrated and embodied, and the mission that it embraced and undertook. The Great Tradition embodies the Apostolic Tradition, i.e., the authoritative source of all Christian faith, the Scriptures, and represents the substance of our confession and faith as has been embraced and affirmed as authoritative by Catholic, Orthodox, Anglican, and Protestant traditions.

As the roots of our orthodox faith, the Great Tradition is grounded in the Apostolic Tradition set in the bounds of the historic orthodox faith as defined and asserted in the ecumenical creeds of the ancient and undivided Church, with special focus on the Nicene Creed. It confesses the Ancient Rule of Faith, the core Christian confession expressed in that adage of Vincent of Lerins: “that which has always been believed, everywhere, and by all.” Moreover, the Great Tradition celebrates and affirms Jesus of Nazareth as the Christ, as Christus Victor, and confidently confesses the Church as the people of God, the "communion of saints," the faithful assembly of believers living and dead who make up the one, holy, catholic (universal), and apostolic community.

As a church passionately invigorated by the presence of the risen Christ, the ancient Church endured the challenges of schism, heresy, paganism, imperial domination, societal immorality, and Gnostic deception. The early Christians articulated a faith that summarized and defended the Apostles’ teaching, and established dynamic worship structures that led its members (many of whom were poor and oppressed) into a living hope and the presence of Christ. With a deep allegiance to the Lord Jesus as the victorious conqueror (Christus Victor) over sin, evil, and the powers, the ancient Church reaffirmed, reenacted, and embodied the life and work of Jesus in the practice of the Christian year. They carefully prepared new converts for baptism into Christ through their candidate training (catechumenate), and celebrated the presence of the living Christ in the rhythm of the Lord’s Day, climaxing in the matchless mystery of the Lord's Supper (the Eucharist). Rather than succumb to societal pressure, these believers lived a faith that enabled them to represent nobly the Kingdom of God in their time, and gave a great pattern and example for us to follow today.

We unashamedly affirm that the Great Tradition embodies the prophetic and apostolic confession of the Scriptures of God’s acts in history in the person of Jesus Christ. Because of this, we are convinced that a critical retrieval of the Great Tradition can enhance our ability today to bear witness to the Kingdom in a troubled and lost society.