Dunn sees a strong contrast between John’s baptism and the baptism in Spirit and fire. He makes this point at length, but here is one example where he writes, “Moreover, in Mark the contrast between the two baptisms is exceedingly sharp:
evgw. evba,ptisa u`ma/j u[dati( auvto.j
de. bapti,sei u`ma/j evn pneu,mati a`gi,w|Å
Here the emphasized words are ‘I’ and ‘He’, ‘water’ and ‘Holy Spirit’. Water is set over against Spirit as that which distinguishes John’s baptism from the future baptism. It would seriously distort the sense of the logion if Spirit-baptism was equated or conflated with water-baptism.” [Dunn, J. D. G. (2011-08-22). Baptism in the Holy Spirit (Kindle Locations 756-760). Kindle Edition.]
However, Anthony Cross insightfully notes, contra Dunn, that the Baptist’s saying is not antithetical parallelism but step parallelism, “in which ‘the second strophe takes up the thought of the first strophe and advances the thought one additional step. As a result, the second line…is an additional, although related, statement that brings the entire saying to its climax and completion’” (citing R. H. Stein). He says, “This sees Jesus’ baptism in the Spirit as the climax/fulfillment of John’s baptism not its antithesis” (“Spirit- and Water-Baptism,” 131).
Stein adds, “[These two baptisms] are not portrayed in Luke-Acts (Luke 3:16; Acts 1:5; 11:16) as standing in opposition to one another but in apposition. Christian baptism is not exclusive, but inclusive, with respect to the baptism of John; the former is not only a baptism of repentance with water, but a baptism of repentance with water and the Holy Spirit as well” (“Baptism in Luke-Acts,” 36).