Question:

Could you please demonstrate from the scriptures the OPC's position that baptism is the sign and seal of the New Covenant, which replaces the Old Covenant sign of circumcision? Thanks.

Answer:

The manner in which you ask your question tells me that you accept the fact that circumcision was a sign of the covenant before Christ came.

It was a "sign" because in itself the physical act was just the cutting of flesh. It's meaning and significance were given to it by the Lord, who said, "I will establish My covenant between Me and you and your descendants after you throughout their generations for an everlasting covenant, to be God to you and to your descendants after you. ... This is My covenant, which you shall keep, between me and your descendants after you, every male among you shall be circumcised" (Gen.17:7,10). "This is My covenant" must mean "this signifies My covenant", since God's covenant with His people did not consist merely in the cutting off of foreskins (similar to our Lord's saying of bread and wine, "This is My body ... this is My blood ..."), but in promises and demands all summed up in "I will be God to you and to your descendants after you."

The Lord sovereignly revealed, established, and determined the terms and signs of His covenant with His people. As the covenant Lord it is within His power and right to alter those terms as pleases Him. He altered the outward administration of this "everlasting covenant" when He brought Abraham's descendants before Him at Sinai and greatly enlarged the content, terms and signs of the covenant (adding the law and ceremonies).

The Lord calls this an "everlasting covenant". This cannot mean that unbelieving Jews today are still party to this covenant. The Lord cut them off as a nation by word (Matt. 21:33-46) and deed (destruction of Jerusalem in 70 A.D.). He enlarged the bounds of His covenant people by gathering in Gentiles to the ends of the earth (Great Commission, Pentecost, Rom. 11:15-24).

In this age Jews and Gentiles who believe in Christ are heirs to the covenant and promises made to Abraham and his descendants for an everlasting covenant (Rom. 4:9-18). The identifiers of the old covenant people of God are applied to the church of Christ, Gal. 6:15, Eph. 2:11-22, Phil. 3:1-3, 1 Peter 1:15,16, 2:4-10, to the exclusion of unbelieving Israel.

There is one people of God through the ages, and once again (with the coming, saving work, resurrection, and ascension of our Lord, and His outpouring of the Spirit) He has changed the outward administration of His everlasting covenant. The everlasting covenant made with Abraham continues, but obviously circumcision is no longer the initiatory sign of that covenant.

What God-given ritual answers to circumcision as an outward sign of belonging to God and being an heir to His promises? The only possible candidate is baptism (as baptism and the Lord's Supper are the only rites commanded by our Lord for His church to observe, and clearly the Lord's Supper does not correlate with circumcision but with the sacrificial sacraments of the OT).

Like circumcision it is a once-for-all initiatory rite; like circumcision it is commanded by the Lord; like circumcision it signifies union with God in the covenant bond ("into the name of the Father and of the Son and of the Holy Spirit"—cf. "I will be your God and you shall be My people," "I will be God to you and to your children after you").

Colossians 2:11,12 bring circumcision and baptism together in this way: baptism ritually unites us with Christ in his burial and resurrection (Rom. 6:3,4—his death, burial, and resurrection), and in that union with Christ we have been circumcised - not ritually but in the cutting of Christ upon the cross (His circumcision/baptism). This passage has been variously interpreted by good students of the Word, so I offer it as suggestive support, not as hard proof.

It may be that in part you are questioning the use of the word "seal" in this connection. That is the word the Apostle Paul uses in Romans 4:11 when he says of Abraham that "he received the sign of circumcision, a seal of the righteousness of the faith which he had while uncircumcised ....." The various signs given by God to symbolize the provisions and promises of His covenant also seal what is promised to believers, whether Jews or Gentiles. As seals they certify the certainty of God's promises and the claim of God upon those who receive the signs.

You will have to judge if I have demonstrated from Scripture to your satisfaction the OPC position that baptism replaces circumcision as the sign of God's covenant with His people. Obviously there is not an explicit verse stating that fact (nor, for that matter, an explicit verse stating the cessation of the law of levirate marriage, which must be inferred from what is stated). But I think I have demonstrated the line of reasoning from the Scriptures that lead to our position: circumcision is no longer the sign of covenant initiation and inclusion (I think all but consistent dispensationalists agree on this); baptism is the sign commanded by Christ for His church which does what circumcision did - marks out and seals those who belong to God in His covenant and signifies and seals to them His promises.

Your question was quite specific, so I will refrain from saying more that would really be ancillary to your inquiry. Some statement could bear greater development, but I'll leave it brief at this point. I do hope this helps you.