Arguably two of the issues that separate confessional Reformed folk from their Baptist friends are the Sabbath and Baptism. For many Baptists (but not all—there are confessional Baptists who agree with the Reformed on the Sabbath

In my response to Tom Schreiner’s critique of the Reformed confession of the Sabbath I wrote, “Underlying Schreiner’s approach to both the Baptism and Sabbath questions is a very large but often unstated a priori conviction about the nature of the new covenant. More on this later. If this conviction about the new covenant fails then not only does Schreiner’s view of the Sabbath fail but so does much of the Baptist argument.”

It’s later now.

Arguably two of the issues that separate confessional Reformed folk from their Baptist friends are the Sabbath and Baptism. For many Baptists (but not all—there are confessional Baptists who agree with the Reformed on the Sabbath) it is a given that the Sabbath was entirely Mosaic and any Sabbath observance expired with the fulfillment of the Mosaic covenant. To the best of my knowledge, Baptists hold that infant initiation belonged to the old covenant and expired with it. Under the new covenant, because of the nature of the new covenant, there could be no infant initiation.

The real, underlying issue here is the nature of the new covenant. Let us then define our terms.

The expression “new covenant” occurs first in Scripture in Jeremiah 31:31. Yahweh says, “Behold the days come when I will cut a new new covenant (berith chadasha) with the house of Israel and the house of Judah.” The new covenant will not be like the “the covenant that I cut with their forefather on the day when I took them by the hand to bring them out of the land of Egypt, my covenant that they broke” (v.32; emphasis added).

Jeremiah makes an explicit distinction between the coming new covenant and a very specific redemptive-historical event: the Mosaic covenant which Yahweh made at Sinai. The new covenant is contrasted with the Mosaic covenant, which v. 32 qualifies as a covenant that was broken. There is another contrast implicit here, between the Mosaic, Sinaitic covenant that was broken and the new covenant that cannot be broken.

Already, in Jeremiah 31 there is a new covenant coming and, implicitly, an old covenant and that covenant is associated with constitution of national Israel and with Moses. Jeremiah continues to qualify the differences between the old and new covenants. Under the new covenant Yahweh will “put my law within them,” i.e., he will “write it on their hearts.” Yahweh will “be their God, and they shall be my people” (v.33).

Under the new covenant, there will be no need for one to say to another, “Know Yahweh,” because everyone will already know him. “For I will forgive their iniquity, and I will remember their sin no more” (v.34).

If we consider the nature of the new covenant, it isn’t entirely “new” at all! Long before Jeremiah, long before Moses, God had promised to Abraham to be a “God to him and to your children” (Gen 17:7).

And I will establish my covenant between me and you and your offspring after you throughout their generations for an everlasting covenant, to be God to you and to your offspring after you.

Scripture repeats the same promise under the Mosaic covenant: “I will take you to be my people, and I will be your God” (Isa 6:7). That promise recurs in Jeremiah before the promise of the new covenant (:23; 11:4; 30:22).

This is perhaps the most fundamental promise of the covenant. It was this sort of language that caused some older Reformed writers (e.g., Cocceius) to define the covenant as “friendship with God.” Of course, before the fall, that friendship was premised upon Adam’s obedience for us. After the fall, that friendship is premised upon the obedience of Christ the Last Adam in place of his elect (Rom 5; 1 Cor 15).

Thus, whatever is new about the new covenant, new cannot mean “never happened before” or “never before promised” or “a relationship with God” or “a spiritual state” that has never existed before in redemptive history. Yahweh was a God to Abraham and to his children for most of 500 years before Moses. The promises of the Abrahamic covenant, which had already been expressed relative to the land and a national people (see Gen chapters 12 and 15; there are national and land promises in chapter 17 also) came to expression in a temporary national covenant inaugurated at Sinai.

That national covenant, however, does not exhaust the covenant promises of God. The Apostle Paul says (Gal 3) that the national, Israelite, Sinaitic covenant, the Mosaic covenant was a temporary addition, a codicil, added to the Abrahamic promises. That temporary national covenant expired with the death of Christ (see also all of Colossians and Hebrews).

The other thing to be noted is that the promises of Jeremiah 31 are cast in Mosaic, typological, and prophetic categories. We need to read it the same way we read prophetic literature generally. The old covenant prophets were writing to God’s national covenant people. Promises that looked forward to his saving acts and words in history, chiefly in the incarnation of God the Son, were cast in Mosaic terms. Failure to recognize this fact lies behind much confusion in biblical interpretation and biblical theology. For one thing it has caused many Christians to look forward to a re-establishment of the old, Mosaic covenant in history, after the incarnation of the Christ, complete with temple and sacrificial system. Such an expectation, of course, is flatly contrary to the explicit teaching of the NT (Eph 2). In Christ the dividing wall has been broken down. In Christ there is no Jew or Gentile (Gal 3).

The contrast, then, in Jeremiah 31 is not between Abraham and the new covenant but between Moses and the new covenant. The novelty or newness of the new covenant is measured relative to Moses, relative to the national covenant made with Israel at Sinai, and not with Abraham and the covenant promise God gave to him: I will be a God to you and to your children. That promise remains intact. The promise is not Mosaic, it is not old, and it is Abrahamic.

(to be Continued in Part 2)

R. Scott Clark is Professor of Church History and Historical Theology at Westminster Seminary in California (see his full bio here). This article first appeared at Scott’s Heidleblog and is used with permission.