The fact is that even pagans can speak infallible Truth, such as the one Paul quoted in Acts 17. Thus the SS evangelical certainly can believe that one can interpret Scripture infallibly, but not as possessing ensured formulaic infallibility, so that whatever he has or ever will speak according to a certain scope and subject-based formula is and will be infallible/without error.
And as souls knew of a Truth that certain men and writings were of God before there ever was a magisterium which uniquely claimed infallibility, (Dan. 2:47; Jn. 6:14; 7:40; 1Co. 14:25) and that such knowing of a Truth is the only definition of souls infallibly knowing Truth, then we can present this as:
The fact you seem to be missing or ignoring is that in all the instances you cited where "souls knew of a Truth that certain men and writings were of God" were due to either divine intervention and/or the intervention of Jesus (cf Dan 2:47, Jn. 6:14; 7:40; 1Co. 14:25) or by the instruction and guidance of St. Paul (Acts 17:16 onward). You'll note in all these instances, the people in question don't come to their revelatory moments via reading the Scriptures. They come to greater knowledge of God via instruction, either from divine revelation, from Jesus, or from St. Paul.
Let's pause and reflect on that for a moment: All the cases you cited are not of anyone "studying" the Scriptures. They are either divine intervention, or acts of teaching.
I suppose one could bring up the case of the Bereans earlier in the chapter of Acts (17) but this is just another example of teaching. This is teaching coupled with Scripture to be certain, but St. Paul didn't just throw a copy of the Scriptures at the Bereans and leave them alone. They studied it, with his help.
Now you may disagree at this moment, but that's your disagreement based on your opinion. We've been down this road you and I, so I won't belabor it. I'll leave it to any objective dispassionate lurker to decide for himself, if you are just giving your opinion and claiming it's "Scripture" or if you are really "just giving Scripture" in reply.
Overall, the main point is that you haven't been able to substantiate a reason to substitute the original Premise 4 for your own. Again, no one disagrees that before Christ, there was no Magisterium. At least not one that could be said to be "infallible". I already said before, that the people in the OT who came to a greater knowledge of God did so via HIS help, not through any "power" or "magisterium".
God's plan is not to leave us dependent upon such moments, such intervention on His part. This is actually the reason for the Incarnation. He became Man precisely because He wishes to work with man to save man. It wasn't just to suffer and die; it was to become part of our existence so as to lead us to a greater way of living now. Otherwise, we remain as lost as the people in the OT.
Whether or not it's admitted, Premise 4 is indeed the Protestant/non-Catholic Christian approach. There is no way it can't be; unless of course one doesn't wish to admit that when one reads the Bible and comes to some conclusion about what's in there, then one is indeed "interpreting" it. And since everyone who reads the Bible is a human, then it's a "human interpretation".
You'll note in all these instances, the people in question don't come to their revelatory moments via reading the Scriptures.
Wrong, while examples can be given of coming to revelatory moments via reading the Scriptures, the fact you seem to be missing or ignoring is that in every case in the OT alone, not exceptions, souls came know that the OT Scriptures (by which Christ established His Truth claims) were of God without ensured magisterial infallibility as per Rome.
And likewise in every case they realized that OT men were of God without an IM, and which is how the NT church began, not under veracity of Truth claims being based upon the premise of ensured perpetual magisterial infallibility as per Rome! Under which that suddenly becomes necessary.
Rather, souls were convinced that Christ was the Messiah, and of the Truth of the Gospel in the light of Scriptural substantiation. Thus it was tripartite Scripture that the Lord substantiated His mission by to the disciples, and opened they eyes to them. (Lk. 24:44,45)
They come to greater knowledge of God via instruction, either from divine revelation, from Jesus, or from St. Paul.
Whether knowing there is a God and His in essence by nature, (Rm. 1:19,20; 2:14) or by Scripture (and recognizing it as being of God), or via preaching, the point is that a perpetual infallible magisterium was not essential, nor even the norm, as it did not exist before a church even existed, nor after despite Rome presuming it.
Let's pause and reflect on that for a moment: All the cases you cited are not of anyone "studying" the Scriptures.
Which convincing by Scripture certainly can be shown, (Acts 17:11; 18:28; 2Tim. 3:15) while certainly souls can also be convinced something is of God without the Scriptures, thus the pagans in Rm. 1 were without excuse for their idolatry.
And before Scripture began to be penned, God spoke in a very limited way to a limited amount of people. But once the Law was given, then as written, Scripture became the transcendent supreme standard for obedience and testing and establishing truth claims as the wholly Divinely inspired and assured, Word of God. As is abundantly evidenced
I suppose one could bring up the case of the Bereans earlier in the chapter of Acts (17) but this is just another example of teaching.
Wrong again, as they searched the Scriptures in order to ascertain the veracity of apostolic teaching, the very thing a faithful RC is discouraged from doing (for that purpose). Disagree if you want, and i will show you.
St. Paul didn't just throw a copy of the Scriptures at the Bereans and leave them alone. They studied it, with his help.
Actually, Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures, (Acts 17:2) while the Bereans received the word with all readiness of mind, and searched the scriptures daily, whether those things were so. (Acts 17:11)
It remains that none of what you have said supports the necessity of an IM in order to what what is of God, but instead even the infallible Lord as well as His disciples established their Truth claims upon evidence, providing Scriptural substantiation in word and in power, versus the fact that they simply spoke it being a guarantee that it was True, though since Christ was God in the flesh, this was true. Note also that the polemical supports for an "infallible" Cath teaching are not themselves covered under the "guarantee of infallibility.
I'll leave it to any objective dispassionate lurker to decide for himself,
Indeed. When they find a perpetual IM being essential in Scripture in order to know what is of God, then they need to show us, since no one else has or can.
Overall, the main point is that you haven't been able to substantiate a reason to substitute the original Premise 4 for your own.
What! Talk about being stubbornly committed to what you want to believe despite the evidence! How can "The Holy Scriptures cannot be infallibly interpreted by any human authority today" be supported when the Scriptures testifies to souls knowing what Scripture both is and means but without an IM, while the poster himself allows that "there are plenty of historical, mathematical, and scientific facts which are beyond speculation." But somehow no one is able to understand even what Thou shalt not commit adultery" without an IM? What an excuse souls will have on judgment day.
Note that neither the RC nor you can simply argue that mere human instrumentality is essential, but that the ensured perpetual magisterial infallibility is.
He became Man precisely because He wishes to work with man to save man. It wasn't just to suffer and die; it was to become part of our existence so as to lead us to a greater way of living now. Otherwise, we remain as lost as the people in the OT.
Christ gave more grace, with a better atonement, high priest and covenant, as Hebrews states (keyword "better"), yet some souls were saved in the OT and some souls are also lost in the NT, but what is missing from the list of better things ensured perpetual magisterial infallibility as per Rome, which is simply read into the NT based upon the fallacious premise of necessity.
Whether or not it's admitted, Premise 4 is indeed the Protestant/non-Catholic Christian approach.
Wrong, as no matter how much you may desperately want to believe it, the fact is that "The Holy Scriptures cannot be infallibly interpreted by any human authority today" is a straw man, as it precludes anyone from making a correct, infallible "beyond speculation" interpretation of Scripture, when we see the NT church itself beginning because souls had correctly understood both writings and men as being of God, and not on the basis of ensured perpetual magisterial infallibility. And even pagans can believe in God so surely in the light of natural revelation that they are without excuse.
You need to return your pasted polemic. What the polemicist needs to argue is that "No human authority can presume to infallibly interpret the Holy Scriptures today on the basis of ensured infallibility," but then he must reason that this is essential for souls to know something "of a Truth." Which remains a novel premise in Scripture.