V.1-2 Notice three things: (1) the whole political world in motion (v. 1); (2) the confusion of the Jewish religion (two high priests); (3) “the word” coming out of the wilderness — not the temple.
V.3 All the prophets of the Old Testament had tried to lead the disobedient nation back to the law and to the ordinances given by God. But all had failed.
V.7 John knows that their hearts are not right, and speaks very sternly. This is not Christian baptism, though performed in the same way. This was a baptism of repentance, for the Messiah was coming. The only way He could be received was by repentance.
V.16 John makes it very plain that he is glad to be only the messenger.
V.22 Of course there was no need of repentance with the Lord Jesus, but God shows His approval of what was being done. We see the Trinity here.
V.23-28 The genealogy of the Lord Jesus goes back to Adam because Luke’s gospel presents Christ as Son of Man, to the whole world. Matthew’s to the Jews, goes back only to Abraham.