Paul does not describe the shift from the Old to New as a simple shift from external to internal…Paul’s letter is not primarily about individual soteriology, but about the union of Jews and Gentiles in the one new man, Jesus the Christ, and the coming of a new creation through His death and resurrection…All those who share the faith of Abraham are “sons of God” (v. 26), that is, true Israelites (cf. Exod. 4:23)…they are all heirs of the inheritance promised to Abraham, the promise of the Spirit (vv. 28-29)…Baptism into Christ and being clothed with Christ is thus all about incorporation into membership in this new body, the body that is “one in Christ Jesus” (v. 28), the community of those who “are Christ’s” (v. 29)…Circumcision distinguished between Jew and Gentile, and also between male and female. In the New Covenant, baptism is applied indiscriminately to all who believe – whether Jew or Gentile, slave or free, male or female. Baptism thus symbolizes and enacts the union of Jew and Gentile int he church, ritually marking all the baptized as sons of Abraham.
Peter J. Leithart, The Baptized Body (Moscow, ID: Canon Press, 2007), 45-46.
We do, of course, need to remember that when the word “baptism” refers to the water ritual, the writer is talking about baptism and not merely water. The word “baptism” in this sense is not even equivalent to the action of pouring water or dunking in water. We cannot reduce a wink to a blink, or a wave of the hand to a nervous twitch of the arm, or an execution by lethal injection to a murder…These actions are different because of the intentions and authorization of the actors. So also, baptism involves a particular use of water, a use authorized and commanded by Jesus Christ, and baptism is always done in connection with the word Therefore, the question is never “Can water do this?” but always “Can baptism do this?”
Peter J. Leithart, The Baptized Body, (Moscow, ID: Canon Press, 2007) 32-33.
[M]any believe it is impossible for water to do what the New Testament says baptism does. But this is…often little more than an assumption brought to the text rather than a conclusion derived from it. It is equivalent to saying John’s teaching that “The Word became flesh” doesn’t mean “God became man” because we already know it is impossible for God to become man.
Peter J. Leithart, The Baptized Body, (Moscow, ID: Canon Press, 2007) 30-31.