From The Christ of the Covenants, O. Palmer Robertson, pg. 41.

The New Covenant, promised by Israel’s prophets, does not appear as a distinctive covenantal unit unrelated to God’s previous administrations. Instead, the New Covenant as promised to Israel represents the consummate fulfillment of the earlier covenants. This organic relation of the New Covenant to the covenants of Abraham, Moses, and David finds explicit development both in the Old Testament prophecies concerning the covenant and in the New Testament realizations of this consummating covenant. From either perspective, the New Covenant may be understood in no other way than as a realization of the prophetic projections found in the Abrahamic, Mosaic, and Davidic covenants.