Chapter 27.5

v. The sacraments of the old testament, in regard of the spiritual things thereby signified and exhibited, were, for substance, the same with those of the new.

Why end the section on the sacraments with a statement as to the diversity and unity of old and new covenant sacraments? The reason seems to be to underline once more what is stated so clearly in the opening section: the hermeneutical importance of the unity of the covenant of grace. Circumcision is to baptism what the Passover is the Lord's Supper. Circumcision, as Romans 4:11 insists, was "a sign and seal of the righteousness that he [Abraham] had by faith while he was still uncircumcised." Circumcision was not a seal of Abraham's faith, but of the (covenant) righteousness which he received by faith. Similarly, baptism seals the word of promise of the gospel - union with the death and resurrection of Christ (Rom. 6:1-4). Thus circumcision and baptism are considered as functionally equivalent (Col. 4:11-12), as are Passover and the Lord's Supper (Matt. 26:26-29; 1 Cor. 5:7).

Old covenant sacraments were types and shadows, but they pointed to Christ and his benefits. The hermeneutical importance of this understanding lies in ensuring that the principle espoused in the administration of the sacrament of circumcision carries through into the administration of the sacrament in the new covenant. Thus, Peter on the day of Pentecost delivers a sermon arguing for continuity rather than discontinuity of sacramental administration: "For the promise is for you and for your children and for all who are far off, everyone whom the Lord our God calls to himself" (Acts 2:39).  

Dr. Derek W.H. Thomas is Minister of Preaching and Teaching at First Presbyterian Church in Columbia, South Carolina and Distinguished Visiting Professor of Systematic and Historical Theology at Reformed Theological Seminary.