evangelist
in
The Fountainhead
(Auto-generated)

someone who actively tries to persuade others to accept a belief or cause, especially a Christian preacher who urges people to become Christians

Most often, evangelist refers to a Christian who preaches and tries to win converts, sometimes on television, radio, or at large revival meetings. More broadly, the word can be used for anyone who strongly promotes an idea, product, or cause—such as a “climate evangelist” or a “tech evangelist.” When capitalized as Evangelist in Christian writing, it can also refer to one of the traditional authors of the four Gospels in the New Testament: Matthew, Mark, Luke, and John.