Proselytizing is more a passionate search for something not yet found than a desire to bestow upon the world something we already have. It is a search for a final and irrefutable demonstration that our absolute truth is indeed the one and only truth. The proselytizing fanatic strengthens his own faith by converting others.

Eric Hoffer (1902–1983) American writer, philosopher, longshoreman

True Believer: Thoughts on the Nature of Mass Movements, Part 3, ch. 14, § 88 (1951)
    (Source)