Imagine St. Vincent of Lérins, quill in hand, scroll beneath his arm, standing at the crossroads of modern Christianity. Having once penned the famous canon that true doctrine is that which has been believed everywhere, always, and by all, he now takes up a new, yet deeply challenging task:
To choose, among today’s church traditions, where he will belong.
To do so, he does what he knows best: he looks backward—not for novelty, but for continuity. He’s searching for a Church that still holds the same DNA of the apostolic faith and has allowed that faith to mature—not mutate, not stagnate, but grow into its fullness “according to the same sense and the same judgment.”
A Common Birth: The Regula Fidei
St. Vincent begins at the most basic place—the root. All the branches claim to be born of the same source. In the image, that source is symbolized by a Bible intertwined with a DNA strand: the Regula Fidei, or “Rule of Faith.”
All three traditions—Eastern Orthodoxy, Roman Catholicism, and Protestantism—have the Gospel. That much is clear. The seed was good.
So St. Vincent gives them all a checkmark: they began well. But that’s not enough. The question isn’t who started with the truth—but who stayed faithful as that truth grew.
Step One: Eastern Orthodoxy — Doctrinal Preservation Without Growth
He begins at the bottom of the chart, with Eastern Orthodoxy. At first glance, he is moved. Here is a Church deeply reverent of tradition, guarding the ancient forms with diligence. The child in this lineage has hardly aged — still clothed in the vestments of the fathers, still chanting the liturgies of the early centuries.
But as he observes longer, he grows uneasy. There is beauty in stillness, yes — but the image has not matured. The content remains unchanged, and so does the clarity. The Church has preserved — but not progressed.
His canon did not only ask for consistency. It asked for development “with vigor, not with change.” Here, the vigor seems lacking. The DNA is untouched — but so is the growth.
“The faith was planted,” he says, “but it never bloomed.”
Step Two: Roman Catholicism — Doctrinal Accretion
Next, he examines the middle path — Roman Catholicism. And here, there is clearly growth. The child has become an adult. There is tradition, expansion, elaboration — doctrine reaching into many corners of life. At first, this looks promising.
But then St. Vincent looks closer. The growth has not come without additions. New features. New obligations. Accretions that begin to crowd the simplicity of the Gospel. The DNA is still there — but it’s obscured. The core remains — but it is surrounded by layers that seem unnecessary at best, and distracting at worst.
The Church insists these are natural developments — even necessary ones. But Vincent is cautious. These doctrines were not always believed. And some of them, he fears, might shift the center of gravity away from Christ and His work.
“Growth is good,” he reflects, “but only if it remains true to the original life. This… feels more like mutation than maturation.”
Step Three: Protestantism — Doctrinal Maturation
Finally, he reaches the top — Protestantism. And what he sees surprises him.
Here is a Church that has grown. The child has become a man. There are leaps in understanding, yes — refinements, recoveries, rediscoveries — but no foreign limbs, no artificial structures. The original DNA is intact and visible.
The focus has not shifted from the central truths. Christ is still at the center. Scripture is still the norm. And growth has happened not by addition, but by clarification — a maturing, not a reshaping.
This is what St. Vincent was looking for all along:
-
The same faith,
-
Growing with the same meaning,
-
Expressed with greater clarity,
-
Without distraction from what matters most.
Here, he finds both the Gospel and its proper development — a tree grown from seed, not a statue built from scraps.
St. Vincent’s Choice
And so he steps back. All three traditions share the Gospel DNA. All three sprang from the same source. But only one shows the kind of development his canon describes:
-
Not frozen in time, like Eastern Orthodoxy.
-
Not overgrown with burdens, like Roman Catholicism.
-
But alive, maturing, and centered — like Protestantism.
If St. Vincent were here today, and he followed his own test, he would choose the Church that grows without abandoning, matures without mutating, and clarifies without distracting.
“What was believed at first,” it says,
“we still believe — only now we understand it more deeply.”
That’s doctrinal development. That’s the Vincentian Canon.
And that, he concludes, is Protestantism.
