All Christians trust the Bible, including (especially) the New Testament. But the Bible leads me to the Church.
This happens in two ways. First, the Bible tells me that Christ established a Church and gave her His authority to teach in His name.
So, the Bible sends me forward to the Church, from Christ to His Church as His invention. The Bible also sends me backward to the Church, for the Church is its cause.
It is a historical fact that it was the Church (the apostles) that wrote the New Testament. It was also the Church that defined its contents, its canon — that told us which books did and which books did not belong in the sacred canon, the books that were divinely inspired and religiously infallible and authoritative. How else does any Christian know that the Gospel of Thomas and the Gospel of Judas are not part of the Bible, part of infallible divine revelation, and that James and Jude and Revelation are?
There is one and only one clear answer to that question: by the authority of the Church.
In other words, the Church was both the efficient cause (the author) and the formal cause (the definer) of the New Testament. That is historical data. Let that be premise 1.
But no effect can be greater than its cause (that is logically self-evident and indubitable), and the infallible is greater than the fallible; therefore, the infallible cannot be caused by the fallible. That is also logically evident. Let that be premise 2.
Either the Church is fallible or infallible. That is also logically self-evident. Let that be premise 3.
Therefore, if the New Testament is infallible, the Church must be infallible, and if the Church is not infallible, then the New Testament is not either. Logically, those are the only two possibilities, unless we deny either the historical data (premise 1) or one of the self-evident assumptions (2 or 3).
Go through it again. If the Church is fallible, as Protestants say, she cannot produce an infallible effect in the Bible. And therefore, if the Church is fallible, then the New Testament is also fallible, like its cause. On the other hand, if the New Testament is infallible, as both Protestants and Catholics say, then the Church, which was its cause, must also be infallible. Only if she is infallible can she produce an infallible effect.
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