Throughout Israelite history there had always been a remnant that did not go the way of rebellion against God, but lived according to His Word and His will.
When John the Baptist came preaching and teaching about baptism, he was calling such a remnant to make a public declaration of their desire to follow God in righteousness and faithfulness. Those who came to be baptized by John publicly declared in front of the entire crowd that when they entered the water they were part of the corrupt Judaism, but when they came back up out of the water they no longer identified with the corrupt way of doing things, but were now part of the new order of God which would follow and obey Him in righteousness and justice.
Was John an Essene?
It is because of Johnโs message of baptism and separation from the corruption of Judaism that many scholars believe that John may have been part of a Jewish sect called the Essenes. The Essenes lived in the Judean desert wilderness, and they too believed that Judaism had become corrupt. To separate themselves from the corruption, they moved out into the wilderness to live, work, and worship in a holy community.