What is Covenant Theology?

Covenant theology is all about the faithful and immutable character of God. It sees the whole Bible as a unity. And there is a reason why Reformed theology has been treated as a synonym for covenant theology. It is because the sovereignty and grace of God are highlighted in that unbroken, eternal plan of God to bring glory to himself through the Person and Work of Jesus Christ, who becomes the hero of every dimension of those covenants. Covenant theology is the Bible’s way of describing redemptive history.

Covenant theology is historical. Justin Martyr appealed to the covenant in his argument with Trypho the Jew. This was to show that Gentiles are included in God’s promises to Abraham. The church is made up of the heirs to those promises. The Christian apologetic against Gnosticism in general and Marcionism in particular had to argue for a unified Bible. The covenant was the basic motif in that defense. Irenaeus’ Demonstration of the Apostolic Teaching traces out some precursors to covenant theology. All that to say that Covenant theology cannot be reduced to the invention of the second generation of sixteenth century Reformers or their successors in the following century. Although it is quite true that what was implicit in Zwingli and Calvin became more explicit in Bullinger, Ursinus, and Olevianus later on in the sixteenth century.

Covenant theology is also, well, theological, but in a very holistic way. It is a hybrid of biblical and systematic theology. Biblical theology operates historically, while systematic theology operates topically. One reads and the other summarizes. One traces a line from left to right, the other draws circles around points. Both are necessary. Vos calls biblical theology “the study of the history of special revelation.” The Bible structures itself covenantally. When the biblical authors want to give the big picture of God’s working in history and the gospel, they use the language of a singular covenantal plan: cf. Psalm 89, Hebrews 6-8. This perspective magnifies the single plan of God: his gracious purposes to redeem a people in his Son and to share every spiritual blessing with them: cf. Eph. 1:3, 11).

Basic Definitions and Method

A covenant is an agreement between two or more persons. As one theologian has defined the biblical form, a covenant is “a bond in blood, sovereignly administered” by God. The elements of the covenant are present from the very beginning of the Bible—first explicitly in Genesis 6, but implicitly already in Genesis 2 and 3. One must keep in mind, in first studying covenant theology, that what matters is not the exact term used here and there, but the concept. And the view toward “concept” is derived from its elements once discerned and arranged. This may appear circular at first. However, we must remember how biblical and systematic theology are friends and not foes. They reinforce each other. When we speak of a “concept” of covenant determining how we view a text, we are not conceding that our concept came out of thin air, from elements arbitrarily imposed upon the text. Rather, the elements are gathered from our reflection on a collection of biblical texts. 

An Example of Crucial Texts

Let us begin with a foundational text in the New Testament. It is foundational not because of “where” it is, chronologically speaking, but rather because of how much ground it covers. The Apostle Paul draws a whole-world-explaining parallel between Adam and Christ in Romans 5:12-21. We will not reproduce it here. Simply look down at your Bible. 

Here we will see why covenant theology is synonymous with federal theology. The word federal is from the Latin for “covenant” (foedus), and the word tends to be used when one wants to stress the idea of representation. Let us make three observations: (1) Romans 5:12-21 presupposes that Adam and Christ are heads of covenants. (2) Romans 5:12-21 leads us to conclude that Adam and Christ are heads of covenants. (3) Imputation is the “essential element” in the link — either of guilt or righteousness. To “impute” means to account, reckon, or consider, in a covenantal context, from one person to another. The man (Adam or Christ) acted in a representative way, such that his action (sin or righteousness) is credited by God to the account of all of the members of the Federal Head’s covenant. 

Now this may all sound very familiar to Christians who would not necessarily call themselves “covenantal” in their theology. And of course it should. It is very much “Gospel 101.” But it is set forth with eye toward consistency and comprehensiveness. And that is where the rubber meets the road in one’s overall doctrine. 

Why Covenant Theology Matters 

In his lectures on Covenant Theology, which have become popular (and which I personally benefited from in class at RTS Orlando), Ligon Duncan gave a very helpful, expansive definition of covenant theology, “Covenant Theology is the Bible’s way of explaining: the atonement, the Christians’ assurance of salvation, sacraments, redemptive history, and the dynamic of God’s sovereignty and our human responsibility in living out the Christian life.” He then offered five reasons why covenant theology matters: “Covenant Theology explains and deepens our understanding of … 1. The atonement; 2. Assurance of faith; 3. The sacraments; 4. The continuity of redemptive history; 5. The Christian life.”

To be more specific, covenant theology features two main historical covenants—arguably the covenant of redemption is a third, outside of time—that of works and grace. Within the covenant of grace there are several administrations: with Adam, Noah, Abraham, Israel (under Moses), David, and then consummation in Christ. What is called the “new covenant” is the historical fruition of the promises to Abraham (Gal. 3:8). It reconciles various tensions that no other hermeneutic can: e. g. the unity and diversity of God’s dealing with man, the unconditional and conditional elements of the same (Gen. 17:1-14), divine sovereignty and human responsibility (Ex. 19:5-6, Eph. 2:8-10), the faithfulness of God to the destinies of Israel and the church (Rom. 11), and the creational-cosmic purposes with the redemptive-restorative purposes of God (Gen. 8:20-9:17).

It explains the symmetry between the sacraments of the old and new: Passover with the Lord’s Supper (1 Cor. 5:7) and circumcision with baptism (Col. 2:11-12). It also best explains the relationship of Christ’s atoning work and the old covenant sacrifices, and how it is that Old Testament saints were saved (Heb. 9:15, 10:11-12). It provides a pastoral basis for giving assurance to the fearful (1 Tim. 2:13, Heb. 6:13-20, 10:23) and admonition to the wayward (Heb. 6:4-6, 10:26-29, 1 Jn. 2:19). In his introduction to Witsius’ classic on the subject, J. I. Packer went as far to say that, “The gospel of God is not properly understood until it is viewed within a covenantal framework.”