He spoke only of repentance (Walter Rauschenbusch)

  The Christian movement began with John the Baptist… In his recorded teaching to the people there is not a word about the customary ritual of religion, about increased Sabbath observance, about stricter washings and sacrifices, or the ordinary exercises of piety.  He spoke only of repentance, of ceasing from wrongdoing.  He hailed the professional exponents of religion who came to hear him, as a brood of snakes wriggling away from the flames of the judgment… The way to prepare for the Messianic era and to escape the wrath of the Messiah was to institute a brotherly life and to equalize social inequalities.

--Walter Rauschenbusch,

Christianity and the Social Crisis

Image source:  Pieter Bruegel the Elder, The Preaching of St. John the Baptist (1566), https://en.wikipedia.org/wiki/John_the_Baptist#/media/File:Brueghel_l'Ancien_-_La_Pr%C3%A9dication_de_Saint_Jean-Baptiste.jpg