true believer

American  

noun

1. a person who has been thoroughly convinced of something.

2. a fanatic, especially a religious or political one.

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Example Sentences

Eliasch added: "Trust me, I am a true believer in also prioritising the sport for the athlete. And here we need to be clever so that in some cases we are a bit skewed."

From Barron's

He gave me an opportunity, plus many other people over the years, and he's a true believer in diversity, not someone that just says it.

From BBC

One look into the night sky, and a true believer could glimpse the turning wheel of Destiny.

From Literature

And so you have to have a leader that is a true believer, so that sort of mentality trickles down.

From The Wall Street Journal

But what matters for Fed independence is that Hassett is a true believer in it, says Harris, the Fed watcher.

From Barron's