Ah, okay, good, thanks for the further info, Gabe (and others).
I think the underlying gospel assurances themselves aren’t damaging, and are rather liberating, which is why converts from one side of Christendom to another truly do (sometimes) benefit in freedoms and spiritual growth by the switches.
One assurance comes down to: I don’t have to do anything to earn my salvation from sin, or even to earn the assurance of my salvation. I don’t have to convince God to save me, or to keep at saving me until He gets it done. God won’t give up on me, even if I sometimes give up on God. God’s faithfulness cannot be invalidated by my unfaithfulness, for God is better and truer than I am.
There are ways to misunderstand and pervert that, even so far as it is stated, much moreso when it comes to trying to explain how some kind of hopeless punishment or fate happens anyway. But it has solid theological roots, and coming to believe it can free a person from some kinds of oppression, especially the legalistic oppression of earning the favor of the judge.
The other assurance comes down to: I don’t have to wonder if God intends to save me from sin, and I don’t have to rely on my own feelings of being chosen or anything else that could in theory be a mistake or self-deception or even divine deception. God intends and acts to save everyone, regardless of who they are, and everyone certainly includes me and certainly includes everyone I love. God certainly doesn’t love them less than I do, and my love for them, especially my saving love for them, isn’t some kind of passable mistake which I may have to be corrected about.
There are ways to misunderstand and pervert that, even so far as it is stated, much moreso when it comes to trying to explain how some kind of hopeless punishment or fate happens anyway. But it has solid theological roots, and coming to believe it can free a person from other kinds of oppression, especially the legalistic oppression of a judge being “arbitrarily” (in the corrupted sense of that term) and immutably fixed against even trying to have mercy on set of persons whose identity will be revealed later and who because of the judge never stood any chance of being saved.
Both kinds of assurance, notice, can rightly inveigh about the other side having legalistic oppression, just of different kinds.