@MoreCoffee
Concerning your Catechism we are told that the 'transmission of Divine Revelation' to man is accomplished in two ways. The two ways are, 1.) orally 2.) written. See Catechism #(74), (75), (76). The second of these, 'written' are the Scriptures.
These two ways, orally and written, were entrusted to 'apostle's' to preach. And to preserve this Revelation, you have the 'apsotolic succession' continuing till the end of time. Catechism #(77)
It is this 'transmission of Divine Revelation' which involves 1.) orally 2.)written and 3.) apostolic succession which is defined as 'Tradition'. And it is this 'Traditon' that Rome bases it's faith.
Catechism #(78) "The living transmission, accomplished in the Holy Spirit, is called Tradition, since it is distinct from Sacred Scripture, though closely connected to it. Through Tradition, the Church, in her doctrine, life, and worship perpetuates and transmits to every generation all that she herself is, all that she believes...."
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