**Contarini
That last sentence succinctly summarizes the problem I have with your posts and those of a lot of other folks on this forum. You are strengthening Protestants in their error, because they imagine that Catholics accept the truth of the Faith based on very weak arguments.**
What you are saying here does not make any sense. According to Aquinas, the arguments of Scripture should convince the faithful even when they cannot convince the adversaries of the faithful. Do you regard yourself as an adversary of the faithful?
“The sole way to overcome an adversary of divine truth is from the authority of Scripture—an authority divinely confirmed by miracles.”
The second quote you cite does not refer to the infallibility of Christ’s Church. It ends with this sentence.
**Hence it is proper to the believer to think with assent: so that the act of believing is distinguished from all the other acts of the intellect, which are about the true or the false. **
What has that got to do with infallibility of the teachings of our faith? We believe, we assent, we know the Holy Spirit guides us infallibly in the teachings of the Church or else all is lost. We might as well doubt or disbelieve all the teachings on the ground that we cannot make out of them a demonstrable science.
Moreover, just before Aquinas died he is reputed to have said concerning his own writings:
“Thee have I preached; Thee have I taught. Never have I said anything against Thee. If anything was not well said, that is to be attributed to my ignorance. Neither do I wish to be obstinate in my opinions, but if I have written anything erroneous … I submit all to the judgment and correction of the Holy Roman Church, in whose obedience I now pass from this life.”
If this is not an affirmation of the infallible teachings of the Church, what is?
Correct me if I mistake your argument. Do you believe that Lutheran teachings might be false? If you do, then why are you arguing for something that is doubtfully true? If you do not believe they are in error, then you must believe they are infallibly true. How do you know they are infallibly true when you deny that the Catholic Church infallibly teaches God’s truth? Why is the Lutheran truth infallible because it comes from Luther, whereas the Catholic truth is false because it claims to come from the Holy Spirit?

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