Addressing your observations regarding the Magisterium, ( The magisterium is the official teaching office of the Church, including the pope and the bishops in union with him.)
You are correct.
Catholic Answers:
encyclopedia
Tradition and Living Magisterium
Excerpt: "Holy
Scripture is therefore not the only theological source of the
Revelation made by
God to His
Church. Side by side with
Scripture there is tradition, side by side with the written revelation there is the oral revelation. This granted, it is impossible to be satisfied with the
Bible alone for the solution of all dogmatic questions. Such was the first field of controversy between
Catholic theologians and the reformers. The designation of unwritten Divine traditions was not always given all the clearness desirable, especially in early times; however
Catholic controversialists soon proved to the Protestants that to be logical and consistent they must admit unwritten traditions as revealed. Otherwise by what right did they rest on
Sunday and not on Saturday? How could they regard infant baptism as valid, or baptism by infusion? How could they permit the taking of an oath, since Christ had commanded that we swear not at all? The Quakers were more logical in refusing all oaths, the
Anabaptists in rebaptizing adults, the Sabbatarians in resting on Saturday. But none were so consistent as not to be open to criticism on some point. Where is it indicated in the
Bible that the
Bible is the sole source of faith? Going further, the
Catholic controversialists showed their opponents that of this very
Bible, to which alone they wished to refer, they could not have the authentic canon nor even a sufficient guarantee without an authority other than that of the
Bible."
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