Proselytizer (noun)

A person who seeks to convert others to their own beliefs, especially in religion.

Origin:

Late 17th century (in the sense "new convert to a religion"): from latin proselytus "newcomer" (translating greek prosēlytos), from proserchomai "come to".

Examples:

1. He was a passionate proselytizer for his religion and would often go door-to-door to speak with people about it.
2. She was raised by her parents who were both fervent proselytizers for their faith, and she inherited their passion for spreading their beliefs.
3. The young man was a proselytizer for a new and controversial political movement, eager to convert others to his way of thinking.
4. The group of protesters were all proselytizers for their cause and were determined to spread awareness of their message.
5. The organization was founded by a group of proselytizers who wanted to spread their beliefs and ideas to as many people as possible.