Separate issue. But I would be wonder why earthly division should absolutely, necessarily separate any individual or ecclesial body from Christ.
We’d admonish them to accept the one, holy, catholic and apostolic Faith in its beautiful clarity.

I know. And yet so are other Catholics (including those in the Magisterium!), who come to different conclusions.

'Zactly. Thank you.

Sure thing. I am all about context.
Here’s the whole chapter in its entirety:
CHAPTER IX: Against the Vain Confidence of Heretics.
But, although it is necessary to believe that sins neither are remitted, nor ever were remitted save gratuitously by the mercy of God for Christ’s sake; yet is it not to be said, that sins are forgiven, or have been forgiven, to any one who boasts of his confidence and certainty of the remission of his sins, and rests on that alone; seeing that it may exist, yea does in our day exist, amongst heretics and schismatics; and with great vehemence is this vain confidence, and one alien from all godliness, preached up in opposition to the Catholic Church. But neither is this to be asserted,-that they who are truly justified must needs, without any doubting whatever, settle within themselves that they are justified, and that no one is absolved from sins and justified, but he that believes for certain that he is absolved and justified; and that absolution and justification are effected by this faith alone: as though whoso has not this belief, doubts of the promises of God, and of the efficacy of the death and resurrection of Christ. For even as no pious person ought to doubt of the mercy of God, of the merit of Christ, and of the virtue and efficacy of the sacraments, even so each one, when he regards himself, and his own weakness and indisposition, may have fear and apprehension touching his own grace; seeing that no one can know with a certainty of faith, which cannot be subject to error, that he has obtained the grace of God.
So Trent seems to re-write Paul, “Work out your own salvation with fear and trembling, [and keep on trembling] for it is God who [may or may not actually be doing] works in you, both to [maybe] will and to [maybe] work for his good pleasure. [Good luck, and happy doubting!]”:tiphat: