What could possibly claim to follow last Sunday’s amazing celebration of Pentecost? Not many feast days could rival its grandeur and power. This is probably why Pentecost is always followed by Trinity Sunday. On this Sunday, Christian believers throughout the world intentionally worship and adore the Three-Person Godhead.

Hailed as the “central mystery of the Christian faith” by the Catechism of the Catholic Church, the Holy Trinity is the revelation of the inner life of God. It is the unveiled truth that God, precisely in his innermost essence, is not solitude, but family.

Yes, as surprising as it might be to those who see God as far removed from human life, God dwells as a family, and he invites us to be a part of it. He is a community of divine persons, namely, the Father, and the Son, and the Holy Spirit.

In full disclosure, it took Christian theology centuries to formalize an understanding of this principal mystery. The doctrine of the mystery does not claim to fully explain God since it’s the very nature of God that’s being explored and elucidated and, as the early writer Tertullian argued, “To claim to understand God would in fact claim to be God.”

While the doctrine is as complete as possible in light of the revelation given by God, the composition of the doctrine of the Trinity had a lot of stumbles, catches, falls, clarifications and developments along the way. There were many caricatures and competitors in the formulation of Trinitarian teaching.

Among the many such contrary possibilities, modalism stands out. It holds a position of prominence because it was highly favored in its own day and its refutation can help expose some problems in our world today.

And so, the obvious questions: What exactly is modalism? And how can the argument against this ancient belief help us today?

Briefly summarized, modalism argued that God was only one Person, who reveals himself in three manifestations or masks. God, as it were, simply changes his appearance depending on circumstances or state of affairs.

Modalism’s god is a lonely and singular entity who is a master of disguises. Believers could legitimately wonder about the intentions of such a god. Did he create us because he needs some affirmation? Why does he play games with us? Why does he not give us a sincere revelation of himself?

In the end, modalism’s understanding of God raises serious questions about both internal and relational integrity. It was precisely because of these concerns that modalism was dismissed by the early teachers of the Christian faith. The three-mask god didn’t quite hold up against the revelation of God given by Jesus Christ.

Admittedly, modalism left a residue in an unexpected way. The theological tradition preserved the use of the word “person,” which ironically comes from the Greek word for an actor’s mask. For this reason, Saint Augustine did not prefer the word “person” in reference to the Trinity, but accepted it out of deference to the theological tradition.

In keeping the word, however, Christian theology had to take it out of its historical context and redefine it. This process was one of the most significant acts of enculturation in Western history – as it involved Greek culture, the Roman legal tradition, and Judeo-Christian theology – and led to the birth of the notion of person in the West.

It’s a view that is now widely accepted and used in philosophy, jurisprudence, cultural arts, and debates involving human rights.

In leaving modalism behind, therefore, Christian theology preserved the word “person” but attached a new definition to it coming right from its own treasury of divine revelation. By insisting on three actual, particular persons, and thereby defining person as “a distinct subsistent within a shared nature,” the theological tradition was showing that each person within the Trinity is self-possessed.

Each person is his own person, and not merely a mask. This emphasis is important as a refutation of modalism, but also as a reflection of the transparency and integrity of the Trinitarian God. There’s no peek-a-boo, or guess who, or any such game of smoke and mirrors. Each person is truly the one he claims to be.

This clarity is helpful to our world today, not simply because it gives us a precise formulation of biblical faith in God, but also because it provides us with a strong definition of the inherent integrity of person, whether applied to the Trinity or to a human being. This is significant since an integrity of person leads inevitably to a call for moral integrity.

At a time when radical autonomy is praised and duplicity rewarded in Western culture, the dismissal of modalism and the assertion of the distinctiveness of persons by Christian theology, can assist each of us and societies to regain a higher expression of our own personhood and that of our neighbors.

On this Trinity Sunday, therefore, we can all hear a summons back to integrity: to be who we are, wherever we are, and to uphold the goodness that is brought about by such integrity and openness.