The pronoun refers to 'His salvation'.What does that refer to? Is the comma before it necessary? Thanks as always.
Thanks, and is it necessary to change "that" to "which" in the above sentence?Yes, like grassy I see it as a "which" in disguise.
For me that's a non-defining relative clause, and as such it calls for "which", and the comma should not be removed. The relative clause provides more information about "salvation", but it is not grammatically essential information.
Relative clauses: defining and non-defining - English Grammar Today - Cambridge Dictionary