*Minor differences ignored. Grouped by changes, with first version listed as example.
The baptism of John, was it from heaven, or of men? This was a new ordinance, and John must have his authority for administering it either from God, or from men; and Christ is desirous to know from which he derived it in their opinion; suggesting, that by the same authority John, his forerunner, came baptizing, he himself came preaching and working miracles; See Gill on Matthew 21:25.
baptism of John--his whole ministry and mission, of which baptism was the seal.
*More commentary available at chapter level.