Is the Rule of Faith an aid to understanding the difficult parts of Scripture?
In an age of interpretive diversity, many wonder if there is not some tool or method that can serve believers as a kind of theological umpire. In short, how do we interpret the difficult parts of Scripture? Some have argued that the rule of faith, or regula fidei, functioned as an authority in the early life of the church, serving as an extra-biblical canon for Christians. If this is the case, the argument states, we have precedent for an extra-scriptural, yet authoritative measure of teaching. We need to bear two things in mind when considering the regula fidei: Its content, and how and with whom it was used.
The Rule of Faith as a precis of doctrine
Rather than being an exhaustive doctrinal statement, the rule of faith was instead a synopsis of the fundamental features of orthodox belief. One can go to websites of various Christian ministries and churches, and find a far more extensive doctrinal statement than anything the rule of faith provides. Tertullian’s version is as follows:
Now, with regard to this rule of faith – that we may from this point acknowledge what it is which we defend – it is, you must know, that which prescribes the belief that there is one only God, and that He is none other than the Creator of the world, who produced all things out of nothing through His own Word, first of all sent forth; that this Word is called His Son, and, under the name of God, was seen “in diverse manners” by the patriarchs, heard at all times in the prophets, at last brought down by the Spirit and Power of the Father into the Virgin Mary, was made flesh in her womb, and, being born of her, went forth as Jesus Christ; thenceforth He preached the new law and the new promise of the kingdom of heaven, worked miracles; having been crucified, He rose again the third day;(then) having ascended into the heavens, He sat at the right hand of the Father; sent instead of Himself the Power of the Holy Ghost to lead such as believe; will come with glory to take the saints to the enjoyment of everlasting life and of the heavenly promises, and to condemn the wicked to everlasting fire, after the resurrection of both these classes shall have happened, together with the restoration of their flesh. This rule, as it will be proved, was taught by Christ, and raises amongst ourselves no other questions than those which heresies introduce, and which make men heretics.
Tertullian presents the basic elements of the gospel, the facts about the life, suffering, death, and resurrection of Jesus. But his rule includes nothing related to church order, sacraments, church government or anything but the most cursory references to eschatology. The rule of faith would serve to mark off the boundaries of orthodox Christology and contain elements of soteriology, but nothing beyond this. The Gnostics, Docetics, Valentinians, and Marcionites would all take objection to this rule because of what it said about the person of Christ. Irenaeus’ rule differs somewhat from Tertullian’s, but still serves as a basic outline of faith, rather than a detailed exposition of life and practices in the church:
The Church, though dispersed through our the whole world, even to the ends of the earth, has received from the apostles and their disciples this faith:
[She believes] in one God, the Father Almighty, Maker of heaven, and earth, and the sea, and all things that are in them; and in one Christ Jesus, the Son of God, who became incarnate for our salvation; and in the Holy Spirit, who proclaimed through the prophets the dispensations of God, and the advents, and the birth from a virgin, and the passion, and the resurrection from the dead, and the ascension into heaven in the flesh of the beloved Christ Jesus, our Lord, and His [future] manifestation from heaven in the glory of the Father “to gather all things in one,” and to raise up anew all flesh of the whole human race, in order that to Christ Jesus, our Lord, and God, and Saviour, and King, according to the will of the invisible Father, “every knee should bow, of things in heaven, and things in earth, and things under the earth, and that every tongue should confess” to Him, and that He should execute just judgment towards all; that He may send “spiritual wickednesses,” and the angels who transgressed and became apostates, together with the ungodly, and unrighteous, and wicked, and profane among men, into everlasting fire; but may, in the exercise of His grace, confer immortality on the righteous, and holy, and those who have kept His commandments, and have persevered in His love, some from the beginning [of their Christian course], and others from [the date of] their repentance, and may surround them with everlasting glory.
Again in Irenaeus’ rule, we find nothing concerning church order, sacraments, or other matters of ecclesiastical life. There is perhaps a bit more here about eschatology than we find in Tertullian, but still nothing in the way of a complete doctrinal exposition such as we would find in the homilies or commentaries on Scripture that came from the Fathers. And as Allert notes, “the Rule of Faith was not a fixed universal formula or creed.” The rule was used to silence heretics, not to argue doctrinal or disciplinary points with other Christians. Those who insisted that Jesus was a mere creature, or that he had only seemed to suffer and die, or that there was no connection whatever between the God revealed in the Old Testament and the revelation of himself in the New – this was the audience for the regula fidei.
With whom was the Rule used?
If the rule presents not a detailed guide, but an overview, we might rightfully ask about its value within the Church.
And indeed, the evidence suggests that inside the church, the rule was not applied, for it would have been superfluous to do so. All agreed as to the deity of Christ, his substitutionary death and resurrection. These were the parameters of orthodoxy, and so when disputes arose within the church, the appeal was to Scripture. T.D. Barnes points out that when speaking to Christians, Tertullian’s authority was always the Scriptures. In the Scorpiace, or Scorpian’s Sting, Barnes notes, “His audience was the orthodox Christian community at Carthage, his purpose to strengthen their resolve. As the best form of argument therefore, he selected biblical exegesis.” Tertullian argues for “the resurrection of the flesh according to the Old and New Testaments. Again, however, a preliminary task intrudes: Tertullian must repel attempts to interpret the Bible allegorically. Finally, the exposition of the scriptures proceeds: it is Tertullian’s favorite mode of argument.”
In this preference for Scripture over tradition, it is evident that Tertullian is joined by Irenaeus. Kelly says that “a careful analysis of his Adversus Haereses reveals that while the Gnostics’ appeal to their supposed secret tradition forced him to stress the superiority of the Church’s public tradition, his real defence of orthodoxy was founded on Scripture. [The] ‘canon’, so far from being something distinct from Scripture, was simply a condensation of the message contained in it.” So dependent was Irenaeus’ rule on Scripture that “this rule is not a supplement to the biblical truth derived from the apostles and prophets, nor a tradition of independent material, but a key to interpret the Scriptures which is compatible with the Scriptures as whole.”
Bearing in mind this purpose, then, the rule of faith cannot be cast as an extra-biblical tradition, for the Fathers believed it to be nothing other than a summary of what the Scriptures taught. Hanson agrees that “the idea of the rule of faith as supplementing or complementing, or indeed adding anything whatever to the Bible, is wholly absent from their thoughts; indeed, such an idea would be in complete contradiction to their conception of the relation of rule to Bible.” Nor can it be seen as a tool to bring recalcitrant believers back in line. To deny the deity of Christ or his resurrection was to put oneself outside the faith, outside the body of Christ. These things are what the rule addressed.
Finally, if we are seeking a hermeneutical principle, this also is not part of it. The rule is too brief to expound in any meaningful way how the Scriptures are to be interpreted. In any dialogue about the proper way to interpret the Bible, the rule of faith does not provide any significant guidance. Bryan Litfin writes that “there is hardly any soteriology or bibliology in the Rule, its eschatology is very basic, and its ecclesiology is meager (though we should note that its very existence presupposes a robust view of the church).“ It would be inaccurate therefore to suggest that the rule provides exegetical guidance since it barely touches on these important doctrines. R.P.C. Hanson agrees that the rule “is not even a principle nor a universally received regulation for interpreting Scripture.”
What then, is the Rule of Faith? It is an interesting token of earlier centuries, a summary of orthodox doctrine, but if we’re looking for a reliable guide to biblical interpretation, the Rule of Faith is not it. That task requires far more effort, study, and indeed, community. Coming to a coherent hermeneutic cannot be reduced to a formula. Every believer needs to do the work of study. But that work yields many rewards.
 Tertullian Prescription Against Heretics, 13, http://www.ccel.org/ccel/schaff/anf03.pdf.
 Irenaeus, Against Heresies, 1.10.
 Craig Allert, A High View of Scripture? (Grand Rapids, Baker Academic, 2008), p. 122.
 Timothy David Barnes, Tertullian: A Historical and Literary Study (Oxford, Clarendon Press, 1971), p. 172.
 Barnes, p. 127.
 J.N.D. Kelly, Early Christian Doctrines, rev. ed. (San Francisco, HarperSanFrancisco, 1978), p. 38-39.
 Stuart G. Hall, Doctrine and Practice in the Early Church (Grand Rapids, Eerdmans, 1991) p. 62.
 R.P.C. Hanson, Tradition in the Early Church (Philadelphia, The Westminster Press, 1962), p. 126.
 Bryan Litfin, “Learning from Patristic Use of the Rule of Faith,” in The Contemporary Church and the Early Church: Case Studies in Ressourcement, Paul A. Hartog, ed. (Eugene, OR, Pickwick Publications, 2010), p. 79.
 Hanson, p. 124.