Researched by the Ignaria Editorial Team · Updated 2026-05-17
For the early Church's greatest polemicists, the rule of faith was not a supplement to Scripture — it was the lens through which Scripture must be read, and the benchmark that exposed false teaching. Irenaeus's strategy against the Gnostics in Against Heresies was to show that Gnostic cosmology was incompatible with the rule held by every apostolic church, from Rome to Smyrna to Corinth. Tertullian's On the Prescription of Heretics argued even more sharply: heretics have no standing to appeal to Scripture because they are outside the rule of faith that determines who legitimately inherits the apostolic deposit. Tertullian's legal argument (praescriptio) was that the question "Who owns Scripture?" must be settled before any debate about its meaning can begin — and the answer is the Church that holds the apostolic rule.
The Rule of Faith as the Apostolic Deposit Preserved by the Church
The early Church measured new teachings against the apostolic faith received from the apostles and preserved publicly across the world. Irenaeus describes the Church as receiving this preaching and preserving it as one house despite global dispersion — unified and recognizable wherever it exists. Tertullian locates authority in the apostles themselves, who faithfully delivered doctrine received from Christ rather than introducing anything of their own. Irenaeus further specifies that the plan of salvation was handed down first by public proclamation and then preserved in Scripture — leaving no room for claims of secret or novel tradition.
Ecclesial Unity as the Visible Criterion of Orthodoxy
Division within the Church was understood not merely as a practical problem but as a theological violation that destroys the faith itself. Cyprian argues that anyone who divides the Church through discord destroys the faith, disturbs the peace, and profanes the sacrament. He presses the point further by equating division with dividing the seamless garment of the Lord — something given by Christ himself and not to be rent. To rend the Church is to rend the very conditions under which the rule of faith can be known and preserved.
Scripture Interpreted Within the Ancient Church as the Standard Against Heresy
The rule of faith also functions as the interpretive key preventing Scripture from being misused by those outside the Church. Clement of Alexandria warns that those who follow the heresies adulterate the truth and steal the canon of the Church — presenting heresy as a moral as well as doctrinal failure. He insists that the Scriptures themselves demonstrate how heresies failed while the ancient Church possesses the exactest knowledge. Tertullian adds that the question of who possesses the Scriptures must be settled before any debate about their meaning can begin: heretics outside the apostolic succession have no claim to them.
Temporal Priority and Public Proclamation as Tests of Authentic Doctrine
Finally, the early Church tested doctrine by the principle of temporal priority: authority belongs to what is more ancient, and corruption belongs to the side convicted of later origin. Tertullian articulates this as an elemental truth — novelty itself becomes evidence of error, since the apostolic deposit was transmitted from the beginning. Tertullian also grounds the rule of faith in the open proclamation of Christ, who spoke openly without any intimation of a hidden mystery. Any teaching requiring secret knowledge contradicts the public character of apostolic transmission and stands condemned by its own novelty.
What the primary sources show
Irenaeus argues that heretics cannot settle disputes by Scripture alone because they interpret it without the apostolic rule of faith — they are "like those who have no key, and who are unable to enter by means of the passages of Scripture." The Church's apostolic tradition, preserved through the succession of bishops, is the authorized framework for reading Scripture; outside it, any reading is possible and no reading is authoritative.
Tertullian's legal argument: the heretics have no right to appeal to Scripture because they do not hold the apostolic rule of faith. "To know nothing in opposition to the rule of faith is to know all things" — inquiry is legitimate only within the rule; outside it, it is not Christian inquiry at all. The apostolic churches are the owners of Scripture; others are squatters. (ANF-03)
As I have already observed, the Church, having received this preaching and this faith, although scattered throughout the whole world, yet, as if occupying but one house, carefully preserves it.
We have learned from none others the plan of our salvation, than from those through whom the Gospel has come down to us, which they did at one time proclaim in public, and, at a later period, by the will of God, handed down to us in the Scriptures, to be the ground and pillar of our faith.
But what unity does he keep, what love does he maintain or consider, who, savage with the madness of discord, divides the Church, destroys the faith, disturbs the peace, dissipates charity, profanes the sacrament?
Who, then, is so wicked and faithless, who is so insane with the madness of discord, that either he should believe that the unity of God can be divided, or should dare to rend it — the garment of the Lord — the Church of Christ?
For we must never, as do those who follow the heresies, adulterate the truth, or steal the canon of the Church, by gratifying our own lusts and vanity, by defrauding our neighbours; whom above all it is our duty, in the exercise of love to them, to teach to adhere to the truth.
Now what is to settle the point for us, except it be that principle of time, which rules that the authority lies with that which shall be found to be more ancient; and assumes as an elemental truth, that corruption (of doctrine) belongs to the side which shall be convicted of comparative lateness in its origin.