Why I remain convinced of 1689 Federalism (related to quoted post below) 1) The text does not merely say the New Covenant will have more regenerate members than the old. It identifies its covenant people by universal covenant blessings: “they shall all know me,” God’s law written on their hearts, and sins remembered no more (Jer. 31:33–34). Hebrews 8 quotes this as the reason the New Covenant is not like the covenant made at the Exodus. An external New Covenant membership containing people who lack these blessings has to be demonstrated from elsewhere because it is not apparent in Jeremiah’s description. 2) Paul certainly teaches one saving promise culminating in Christ, but he explicitly distinguishes that promise from the later Mosaic covenant: “the law, which came 430 years afterward, does not annul a covenant previously ratified” (Gal. 3:17). Then in chapter 4 he actually speaks of “two covenants” (4:24). Continuity of the promise is not identity of covenants. That distinction is basically the 1689 Federalist point. 3) Colossians 2 does not say baptism replaces circumcision. Paul connects baptism with the circumcision made without hands, defined as the putting off of the body of flesh “by the circumcision of Christ.” And the baptized are raised with Christ “through faith.” The correspondence is between physical circumcision and its Christological fulfillment, with baptism signifying participation in that fulfillment. To say that baptism simply replaces circumcision skips the reality Paul places between them: regeneration/union with Christ. 4) The Jerusalem Council argument is an argument from silence resting on the very continuity being disputed. Acts 15 asks whether Gentile believers must be circumcised and keep Moses. The apostolic answer is not, “your children retain the same covenant standing, but the sign has changed.” Rather, the controversy is resolved from the fulfillment of the promises in Christ and the inclusion of believing Gentiles. One cannot establish continuing infant covenant membership by saying the apostles never explicitly abolished it when whether that membership continues is precisely the question. 5) The proselyte-baptism argument is weakest for an even more fundamental reason. Even granting the historical reconstruction, an extrabiblical Jewish practice cannot establish the subjects of a sacrament instituted by Christ. Christian baptism receives its theological meaning from Christ’s institution, death and resurrection, union with Him, and the apostolic interpretation, not from an assumed continuation of later Jewish proselyte customs.

Many in the PCA treat a desire to contextualize as a progressive drift that accommodates culture, forsaking fidelity to Scripture & our standards. But what is contextualization? A 🧵on what @timkellernyc says in his book on preaching & Center Church. 1/11