Study Guide: Believer Baptism in the Reformed Baptist Tradition

I. Foundational Document

The 1689 Second London Baptist Confession of Faith — Chapter 29: "Of Baptism"

The Confession, structurally paralleling the Westminster Confession (1646) and Savoy Declaration (1658), deliberately diverges on sacramentology. Chapter 29 is the locus classicus for Reformed Baptist baptismal theology.

Key Paragraphs (summarized):

Paragraph	Content
29.1	Baptism is an ordinance of the New Testament, instituted by Christ, as a sign of fellowship with Him in His death and resurrection, of remission of sins, and of yielding to God through Christ.
29.2	To be administered only to those who actually profess repentance toward God, faith in and obedience to our Lord Jesus Christ.
29.3	The outward element is water, the administrator a qualified ordained person of the same sex as the candidate is implied.
29.4	Immersion ("dipping") is the proper mode — the body dipped into water in the name of the Father, Son, and Holy Spirit.

Study note: Note the carefulness of 29.2 — the Confession does not merely say "adults" but "those who actually profess repentance and faith." This guards against both infant baptism and mere age-based baptism. 29.4 is more explicit on immersion than the Westminster Confession.

Reading the Confession alongside its sources:

Compare WCF 28 (paedobaptist) vs. 2LBCF 29 — note where and why Baptists revise.
Compare with the First London Confession (1644/1646) — particularly Article 39–40, which is more terse but equally credobaptist. Notice the development between First and Second London on covenant theology depth.

II. The Core Theological Argument: A Reformed Baptist Account

Reformed Baptist baptismal theology is not simply "we baptize adults." It is built on a particular reading of covenant theology that denies the strict parallel between circumcision and baptism maintained in classic paedobaptist federalism.

The Three Load-Bearing Arguments

1. The New Covenant is Unmixed (Jeremiah 31:31–34; Hebrews 8:8–13) The New Covenant, unlike the Abrahamic and Mosaic administrations, contains only the elect. All members "know the Lord," have their sins forgiven. Since covenant membership is now restricted to the regenerate, baptism — the New Covenant sign — properly applies only to those credibly professing faith.

2. Circumcision ≠ Baptism as Direct Typological Successor Paedobaptists argue baptism replaces circumcision (Gen 17; Col 2:11–12). Reformed Baptists respond:

Circumcision was the sign of the Abrahamic covenant (which included both spiritual and national/earthly dimensions and both elect and reprobate members).
Baptism is the sign of the New Covenant, which is exclusively spiritual and salvific.
The New Covenant sign is not a direct replacement of circumcision but a new sign for a qualitatively different covenant.