In chapter 9 the author identifies the fatal flaw of Paedobaptist covenant theology, it is the fact that they label the Mosaic Covenant of Works as a covenant of grace. The fact that the Mosaic contains covenant breakers and condition is contrary to the notion of a covenant of grace as he sought to argue in the previous chapters. In chapter 9 he also looks to “the problem of making the covenant of grace breakable.” (p. 121)
The next two chapters he examines the deficiencies (chapter 10) and purpose (chapter 11) of the Old Covenant.
In Chapter 12 and 13 he writes about the discontinuity between the Old and New covenants. He identifies four aspects in which they differ:
- Different Participants – Based from the Abrahamic promise of “to you and your seed” Presbyterians argue for the continuity of that promise for all the administrations of the Covenant of Grace, unless there is a prohibition or exclusion of infants. But Johnson counters by saying that the reference to “you and your seed” Paul sees as referring to Christ in Galatians 3:15, therefore this promise is not referring to unbelieving Jews, rather to Christ and those who are in Him (Gal 3:29). The promises were made to Abraham and his seed, which is Christ and all who are in Him.
- Different Substances – This is the obvious conclusion if the Mosaic was not an administration of the Covenant of Grace. While the New and Mosaic covenants are two different covenants and not merely administrations of the Covenant of Grace, that does not mean that they don’t have similarities. The Old Covenant foreshadowed the New Covenant. The earthly things pointed to the spiritual realities of the New Covenant. For example, people entered the Old Covenant by their birth within the nation of Israel, but people enter into the covenant by the new birth – by being born from above. Under the Old Covenant circumcision was an outward and fleshly act, while under the New Covenant it is a spiritual thing and it refers to regeneration. Johnson believes that Paedobaptists are wrong to “cling to the shadows of infant circumcision. In so doing, they mix the ineffectual and temporary shadows of the old covenant with the eternal realities and power of the new covenant.…by connecting infant circumcision…with baptism.” (p. 157)
- Different Durations – The Old Covenant was destined to pass away. God did not intend it to be eternal. The fact that it had passed away is clear for example from Hebrews 8:13. While the New Covenant is called the “eternal covenant” in Heb 13:20. The Old Covenant was abolished in order to establish the New (Heb 8:6-11).
- Different Efficacies – “The old covenant did not contain or offer grace (unmerited mercy – justification, or inward power – sanctification) to its members, while the new covenant does.” (p. 163) The efficacy of the Mosaic was depended upon the obedience of the people as can be seen in many places in the Old Testament (e.g. Ex 19:5-6; Deut 30:19; Gal 3:10). But the efficacy of the New Covenant is not depended upon man, but upon the God-Man. It is He who provides that which God requires. He is the Covenant Keeper and by His doing we are made righteous and have a loving relationship with God. Chapter 13 is dedicated to the discussion of this topic along with questions concerning the law, justification and sanctification established by the New Covenant....