Those who wrote the Word of God (including the Old Testament which was already in existence long before there was a Pope) were simply believers. Nowhere do they refer to themselves as catholic.
The Scriptures (Old and New Testaments) were inspired by the Holy Spirit. Thus they are the Word of God. Nothing else is as authoritative including the catholic pronouncements about Mary.
All Christians were Catholics (I am including Orthodox with the Catholics because they the same sacraments), before protestants came along over 1,500 years after Christ died. The Catholic Church canonized the New Testament and the OLD TESTAMENT. The Catholic Church determined what books were divinely inspired and what books were not. The same Bible that protestants claim Catholics don’t know was compiled by Catholics. It is a Catholic document. Without the Catholic Church it wouldn’t exist. Sacred tradition goes hand in hand with scripture. Only protestants have a hard time figuring that out.
When Yeshua referenced the “Scriptures” he meant the “Old Testament” only.
When Paul and Peter said “scripture” they also only meant the old testament.
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