Could moderators please move "Soteriology" as a tag-synonym for "Salvation"?
Or perhaps, could explanations be given (in tag descriptions) showing how these tags are different and how they should be used?
Tags should always use the "industry standard" technical terms. In this case soteriology would be the best candidate for the tag. Anything else that people frequently tend to come up with should be synonyms of the technical term.
I have gone ahead and merged salvation into soteriology. For future reference, you or anyone else that wants to suggest synonyms can do so from this page, after which they can be voted on and approved by a couple other community members or a moderator. The tag descriptions of course can be edited at any time by almost anybody with a modicum of reputation.