Herod's descendants divided the sacred land between them, and that
the very high-priesthood was illegally administered, so that such a
pair as Annas and Caiaphas held it in some irregular fashion between
them? It was clearly high time for John to come, and for the word of
God to come to him.

The wilderness had nourished the stern, solitary spirit of the
Baptist, and there the consciousness of his mission and his message
'came to him'--a phrase which at once declares his affinity with the
old prophets. Out of the desert he burst on the nation, sudden as
lightning, and cleaving like it. Luke says nothing as to his garb or
food, but goes straight to the heart of his message, 'The baptism of
repentance unto remission of sins,' in which expression the
'remission' depends neither on 'baptism' alone, nor on 'repentance'
alone. The outward act was vain if unaccompanied by the state of
mind and will; the state of mind was proved genuine by submitting to
the act.

In verses 7 to 14 John's teaching as the preacher of repentance is
summarised. Why did he meet the crowds that streamed out to him with
such vehement rebuke? One would have expected him to welcome them,
instead of calling them 'offspring of vipers,' and seeming to be
unwilling that they should flee from the wrath to come. But Luke
tells why. They wished to be baptized, but there is no word of their
repentance. Rather, they were trusting to their descent as exempting
them from the approaching storm, so that their baptism would not
have been the baptism which John required, being devoid of
repentance. Just because they thought themselves safe as being
'children of Abraham,' they deserved John's rough name, 'ye
offspring of vipers.'