Mark 1:1-4 : The beginning of the story

"In youth, because I could not be a singer,
I did not even try to write a song;
I set no little trees along the roadside,
Because I knew their growth would take so long.

But now from wisdom that the years have brought me,
I know that it may be a blessed thing
To plant a tree for someone else to water,
Or make a song for someone else to sing."

Mark says John is the person who planted trees for Jesus to water. The book starts with a verse - “I will send my messenger before you and he will prepare road for you” (Malachi 3:1) . In the original context, the messenger is to come to purify, to cleanse the holy place before the anointed one came.
Barclay goes on to say that wherever the Christian message is spread, that place is cleansed. He cites two examples, one about Bruce Barton, a journalist who wanted to write articles to expose the evangelist Billy Sunday and the other about the happenings in ‘The Mutiny on the Bounty’. In the former case, Barton followed Sunday to several places and found that the moral structure of the place had changed after Sunday's preaching. The society was more peaceful and there was less quarrelling. In the latter, Smith, the only mutineer who had survived, read a bible and preached to the natives. Twenty years down the line, an American ship which chanced upon the island found a peaceful community and not a bunch of savages.

John came announcing baptism. During those days baptism was only for gentiles who were being converted to Jewish faith. Each had to undergo the following
1) Circumcision (mark of covenant)
2) Sacrifice (atonement could only be by blood)
3) Baptism (cleansing )
John preached that Jews has gone so astray from the true faith that they also had to be baptized.
Baptism was accompanied by confession. Confession is complete when a person confesses to 3 people.
1) To himself
2) To those whom he wronged
3) To God
in the same order