Romans 6
Union with Christ — Dying and Rising in Romans 6
Sanctification flows from union with Christ. Rom 6:1-11 argues that those baptized into Christ were baptized into his death, so that "we too might walk in newness of life." Sin's dominion is broken because the believer has died and risen with Christ. Calvin made union with Christ the center of applied salvation, holding justification and sanctification to be distinct but inseparable gifts received in the one Christ. The same union grounds the Catechism's theology of life in Christ and the Eastern vision of the sharing in the divine life that Athanasius described. Owen developed the believer's mortification of sin from this union. The baptismal logic of 6:3-4 connects to the Great Commission of Matt 28:19 and to the new-creation theme of Rom 8:1-4, where there is now "no condemnation." Sanctification is the outworking of a gift already given.
Saved by Grace through Faith — Ephesians 2:8-10
Eph 2:8-10 holds together what is often torn apart: "by grace you have been saved through faith... not a result of works," and yet we are "created in Christ Jesus for good works." Salvation is by grace; good works are its fruit, not its root. Augustine's maxim captures the logic all sides own — that when God crowns our merits he crowns his own gifts; the Council of Orange had already excluded any human initiative before grace. Luther seized on the gift-character of faith; Trent taught that this grace is genuinely transformative and bears fruit in love; and the Joint Declaration affirms together that we are saved by grace through faith, not because of any merit of our own. The relation of this gift to the good works of 2:10 is unfolded in Jas 2:14-26. The movement from death to life in 2:1-5 parallels the new birth of John 3:5 and anticipates the new creation of Rom 6:4.
The Trinity in the Great Commission — Matthew 28:19
Matt 28:18-20 commissions the church to baptize "in the name (singular) of the Father and of the Son and of the Holy Spirit." One name, three persons: the baptismal formula is implicitly trinitarian. Augustine's On the Trinity mined this text for the unity of the divine persons, and the Nicene Creed gave the church its trinitarian grammar. Basil and the Cappadocians defended the Spirit's full deity on such baptismal grounds. The baptism commanded here is unfolded theologically in Rom 6:3-4, and the abiding presence of 28:20 echoes the Immanuel of Matt 1:23. The triune name is the church's confession and its commission.
Baptism into Christ — Romans 6 and Matthew 28
Rom 6:3-4 interprets baptism as union with Christ's death and resurrection: "we were buried therefore with him by baptism into death, in order that... we too might walk in newness of life." The sign signifies a real participation. Calvin defined a sacrament as a visible word that seals the promise, and the Catechism treats baptism as the gateway to life in the Spirit. Augustine's debates with the Donatists shaped the church's theology of valid baptism. Baptism is commanded in the Great Commission of Matt 28:19 and grounded in the union of Rom 6:5-11. It is the visible entry into the body addressed in 1Cor 12:13.
The Church as the Body of Christ — 1 Corinthians 12
1Cor 12:12-27: "for just as the body is one and has many members... so it is with Christ." By one Spirit all are baptized into one body, and the diversity of gifts serves the common good. Augustine's totus Christus — the whole Christ, head and members — expresses this unity, and Calvin treated the church as the mother of believers. The Catechism develops the body-of-Christ image for the communion of saints. The Spirit who distributes gifts here is the same Spirit of John 15:26 and Pentecost in Acts 2:17. The one baptism into one body connects to Rom 6:3 and Eph 4:4-6.