Blog 71: 2.10.1 - 2.10.7
John Calvin is a covenant theologian. That is to say, he comprehends the whole biblical teaching on salvation under the category God's gracious covenant for the redemption of his people in Christ.
While Calvin recognizes differences between the Old and New Testaments, he emphasizes continuities in the administration of God's grace. In this section of the Institutes, he argues that the old and new covenants are fundamentally the same. Whether they lived before or after the coming of Christ, the people of God are all adopted into the same family, all bound by the same law, all saved by the same grace, and all promised the same everlasting inheritance.
To prove the continuity of the covenant, Calvin clarifies teaching of the Bible from three common misperceptions about the operations of God's grace in the Old Testament:
First, the blessings that God promised to his Old Testament people were not merely physical and temporal (like the Promised Land, for example), but also, and more fundamentally, spiritual and eternal (like the promise of everlasting life).
Second, the basis for salvation in the Old Testament, no less than in the New, was the mercy of God. The Jews who were saved before the coming of Christ--like the Jews and Gentiles who were saved afterwards--were saved by the free grace of God and not by their own merits. Justification has always been by grace alone.
Third, the Old Testament believers were saved by their union with Jesus Christ, who is the one and only Mediator for the one and only covenant people of God.