We will now identify and discuss four principles utilized by the federal theologians.
1. The Holy Spirit is the Only Infallible Interpreter of Holy Scripture.
As an example of this principle, John Owen says, “The only unique, public, authentic, and infallible interpreter of Scripture is none other than the Author of Scripture Himself…that is, God the Holy Spirit.” Nehemiah Coxe says, “…the best interpreter of the Old Testament is the Holy Spirit speaking to us in the new.” This meant that they saw the Bible’s interpretation and use of itself as infallible and with interpretive principles embedded in it. When the Bible comments upon or utilizes itself in any fashion (e.g., direct quotation, fulfillment, allusion, or echo in the OT or NT), it is God’s interpretation and God’s understanding of how texts should be understood. This often means that later texts shed interpretive light on earlier texts. Or, we could put it this way, subsequent revelation often makes explicit what is implicit in antecedent revelation. This principle led to three more related concepts.
2. The Analogy of Scripture (Analogia Scripturae)
Here is Richard A. Muller’s definition of analogia Scripturae: “the interpretation of unclear, difficult, or ambiguous passages of Scripture by comparison with clear and unambiguous passages that refer to the same teaching or event.” An example of this would be utilizing a passage in Matthew to help understand a passage dealing with the same subject in Mark. This principle obviously presupposes the divine inspiration of Scripture.
The principle of analogia Scripturae gained confessional status as follows: “The infallible rule of interpretation of Scripture is the Scripture itself…” (2LCF 1.9).
3. The Analogy of Faith (Analogia Fidei)
Muller defines analogia fidei as follows:
the use of a general sense of the meaning of Scripture, constructed from the clear or unambiguous loci…, as the basis for interpreting unclear or ambiguous texts. As distinct from the more basic analogia Scripturae…, the analogia fidei presupposes a sense of the theological meaning of Scripture.
An example of this would be interpreting texts that speak of the humanity of Christ in the wider textual-theological context of the incarnation of the eternal Son of God. For example, in Acts 20:28, God is said to have purchased the church “with His own blood.” “Be on guard for yourselves and for all the flock, among which the Holy Spirit has made you overseers, to shepherd the church of God which He purchased with His own blood.” From other texts of Scripture, according to the principle of analogia fidei, we learn that Christ, according to his divine nature, is invisible (John 1:1, 18). So, according to the analogy of faith, we can affirm that God has blood, in so far as the person of the Son has blood, according to his human nature.
The inspired and infallible rule of faith is the whole of Scripture whose textual parts must be understood in light of its theological whole. This insures that the theological forest is not lost for the textual trees.
The principle of analogia fidei gained confessional status as follows: “The infallible rule of interpretation of Scripture is the Scripture itself…” (2LCF 1.9).
4. The Scope of Scripture (Scopus Scripturae)
Terms such as Christ-centered and Christocentric are used often in our day. But what do they mean? The older way of describing the concept these terms point to, the target or end to which the entirety of the Bible tends, is encapsulated by the Latin phrase scopus Scripturae (i.e., the scope of the Scriptures). This concept gained confessional status in the Westminster Confession of Faith, the Savoy Declaration, and the Second London Confession of Faith in 1.5, which, speaking of Holy Scripture, says, “…the scope of the whole (which is to give all glory to God)…”
Reformation and post-Reformation Reformed theologians understood scope in two senses. It had a narrow sense–i.e., the scope of a given text or passage, its basic thrust; but it also had a wider sense–i.e., the target or bull’s eye to which all of Scripture tends. It is to this second sense that we will give our attention.
Scope, in the sense intended here, refers to the center or target of the entire canonical revelation; it is that to which the entire Bible points. And whatever that is, it must condition our interpretation of any and every part of Scripture. For the covenant theologians of the seventeenth century, the scope of Scripture was the glory of God in the redemptive work of the incarnate Son of God. Their view of the scope of Scripture was itself a conclusion from Scripture, not a presupposition brought to Scripture, and it conditioned all subsequent interpretation.
William Ames said, “The Old and New Testaments are reducible to these two primary heads. The Old promises Christ to come and the New testifies that he has come.” Likewise, John Owen said, “Christ is…the principal end of the whole of Scripture…” He continues elsewhere:
This principle is always to be retained in our minds in reading of the Scripture,–namely, that the revelation and doctrine of the person of Christ and his office, is the foundation whereon all other instructions of the prophets and apostles for the edification of the church are built, and whereunto they are resolved… So our Lord Jesus Christ himself at large makes it manifest, Luke xxiv. 26, 27, 45, 46. Lay aside the consideration hereof, and the Scriptures are no such thing as they pretend unto,–namely, a revelation of the glory of God in the salvation of the church…
Nehemiah Coxe said, “…in all our search after the mind of God in the Holy Scriptures we are to manage our inquiries with reference to Christ.”
Their Christocentric interpretation of the Bible was a principle derived from the Bible itself and an application of sola Scripturae to the issue of hermeneutics. In other words, they viewed the Bible’s authority as extending to how we interpret the Bible. Or it could be stated this way: they saw the authority of Scripture applicable to the interpretation of Scripture.Richard Barcellos Grace Reformed Baptist Church Palmdale, CA .
 This is taken from a lecture to be delivered at the Southern California Reformed Baptist Pastors’ Conference 2014.
 John Owen, Biblical Theology or The Nature, Origin, Development, and Study of Theological Truth in Six Books (Pittsburgh, PA: Soli Deo Gloria Publications, 1994), 797, referenced as BTO here on out.
 Coxe and Owen, Covenant Theology, 36.
 Richard A. Muller, Dictionary of Latin and Greek Theological Terms (Grand Rapids: Baker Book House, 1985, Second printing, September 1986), 33, emphasis added.
 Muller, Dictionary, 33. Cf. Walter C. Kaiser, Jr., Toward An Exegetical Theology (1981; reprint, Grand Rapids: Baker Book House, Sixth printing, January 1987), 134ff., where Kaiser fails to distinguish properly between analogia Scripturae and analogia fidei and advocates what he calls “The Analogy of (Antecedent) Scripture.” In the conclusion to his discussion (140), he says, “However, in no case must that later teaching be used exegetically (or in any other way) to unpack the meaning or to enhance the usability of the individual text which is the object of our study,” emphasis Kaiser’s. This is, at worst, a denial of the historic understanding of analogia fidei and, at best, a very unhelpful and dangerous modification of the doctrine. It seems to me that this would mean, for example, that we cannot utilize anything in the Bible outside of Gen. 1-3 to help us interpret it. Since there is nothing in the Bible antecedent to Gen. 1-3, interpreters are left with no subsequent divine use, no subsequent divine explanation of how to understand that passage. This method ends up defeating itself when we consider that Genesis (and all other books of the Bible) was never intended to stand on its own and that the Bible itself comments on antecedent texts, helping its readers understand the divine intention of those texts. Kaiser’s method seems to imply that the exegesis of a given biblical text is to be conducted as if no subsequent biblical texts exist. We must realize that, in one sense, we have an advantage that the biblical writers did not have–we have a completed canon. But we must also realize that the Bible’s use of itself (whenever and wherever this occurs) is infallible. If this is so, then the exegete, using tools outside of the biblical text under consideration, ought to consult all possible tools, which includes how the Bible comments upon itself no matter where or when it does so. If the Holy Spirit is the only infallible interpreter of the Bible, then certainly exegetes ought to utilize biblical texts outside of Genesis to aid in the understanding of Genesis. It seems to me that Kaiser’s proposal would give warrant for exegetes to consult commentaries on Genesis to aid in its interpretation, but deny the use of the Bible itself (which contains inspired and infallible commentary) to that same end.
 See the discussion in Richard A. Muller, Post-Reformation Reformed Dogmatics: The Rise and Development of Reformed Orthodoxy, ca. 1520 to ca. 1725, Volume Two – Holy Scripture (Grand Rapids: Baker Academic, 2003 [Second Edition]), 206-23, where he discusses these distinctions.
 See my forthcoming The Doxological Trajectory of Scripture: God Getting Glory for Himself through what He does in His Son – An Exegetical and Theological Case Study, chapter 5, “Christ as Scopus Scripturae – John Owen and Nehemiah Coxe on Christ as the Scope of Scripture for the Glory of God.”
 William Ames, The Marrow of Theology (Durham, NC: The Labyrinth Press, 1983), 202 (XXXVIII:5).
 John Owen, The Works of John Owen, 23 vols., ed. William H. Goold (Edinburgh: The Banner of Truth Trust, 1987 edition), 1:74.
 Owen, Works, 1.314-15.
 Coxe and Owen, Covenant Theology, 33.