I beleive as 99% of christians beleive that christian doctrine is developed.
The protestant doctrine of righeousness by faith was only developed at the time of the reformation and many times the christian church only looks at a doctrine when a heracy pops up. You cant asnwer a question before its asked.
The same applies to the trinity doctrine hundreds of baptisimal formalia in th efirst few centries had the central theme as the trinity the nicean creed is taken from the creed of ceasarear. Arius was a Jonny come lately is the developement of the doctrine.
I dont beleive the doctrine is depentant on salvation in factr some in the church I attend dont beleive the trinity but they are in the minority.