Doctrine vs. gospel

[jokaec]

"You can't rely on anyone for sure." is her "doctrine" or "gospel".

As far as I know, "gospel" doesn't only mean you believe in but also means you persuade others to believe. That's the only difference between "doctrine" and "gospel" in my context. Am I right? Thank you.

 

[jmichaelm]

A doctrine is a set of beliefs, but the gospel is the specific doctrine of Christ. However sometimes "gospel" is used to indicate that someone believes their doctrine is the only possible correct viewpoint. It might in that case not refer explicitly to Christian doctrine, instead referring to the nature of a divine doctrine.