He wasn't really a "preacher".  But he liked to share his views and ideas.  Soon, people began listening.  It wasn't very many people, but he knew his following would grow.  He was scared, scared that people wouldn't like his ideas, or that he was teaching the wrong things.  Then one day he realized.  Your opinions and ideas are your own.  And while there are times you should keep them to yourself, they are a part of you.  If people hate your ideas, why should you want them to like you?  So he surrounded himself in his following, and eventually it became more of a... community.  He knew he was making people happy, and to him, that was enough.