In this post, we will cover Part 1, Chapter 1, section 2 of the report. This will cover the distinction between substance and administration of the covenant of grace.
The substance of the covenant of grace is the same during all the time of its various administrations, or dispensations. The covenant of grace has its beginning in the protoevangelion of Genesis 3:15, and grows, like a tree from a seed, into a huge kingdom that, with Christ as its Head and King, conquers all spiritual opposition. The substance of the covenant of grace is Christ Himself. Therefore, the covenant of grace is understood to be a covenant of saving grace. Christ as Savior is the substance of it. The writers also note, however, that conditions are also often described as being at the heart of a covenant: change the conditions, change the substance of the covenant.
There is both unity and diversity in the various administrations of the covenant of grace. The administration of the covenant differs going from Old Testament to New Testament as typology relates to the fulfillment of typology. Typology itself is a rubric under which we can organize the entire administration of the Old Testament iterations of the covenant of grace. So, the substance of the various iterations of the covenant of grace (or covenants, as the various dispensations can be called) is the same, even if the typological administration varies.
Although the grace God gave to the people of the Old Testament was true saving grace, the amount and clarity of that saving power was mitigated in the Old Testament times by virtue of the lesser stage of redemptive history. 2 Corinthians 3 is very clear in this regard. We have better access now to the grace and power of God than any Old Testament believer did.