On a recent Sunday, the readings included the Apostle Paul's description to the Corinthians of the functions of the Body of Christ (1 Cor. 12:12-30). In his homily at the Mass I attended that day, the pastor reflected on the appropriateness of St. Paul's choice to liken the relationship between Christ and the members of his Church to a human body. I was especially struck by this insight offered by the pastor: "Christianity, at least in its 'Catholic version,' is most definitely not a religion 'of the Book.' It is a religion of the Person."
Unlike traditions that are devoted to a book, the Catholic Church follows—first, foremost, and without apology—the person of Jesus Christ, its founder. Or, more precisely, we follow Persons: the Father, the Son, and the Holy Spirit. Divine revelation is given to the Church through a book (the Bible), but it is also handed on through persons, both by divinely preserved sacred Tradition and by the Church's divinely established teachers (the magisterium). The book was dependent upon persons to write down what they received by inspiration, to collate the library of books within the book, and to preserve the book for future generations.
This devotion to persons also influences the Church in other ways: With St. Paul, we see Christ in those who are persecuted (Acts 9:4). We serve Christ in the least among us (Matt. 25:40). We defend every human person, from conception to natural death, because they are images of Christ who was "the firstborn of all creation" (Col. 1:15).
Sometimes Catholics must answer a charge by Protestants that all of divine revelation is to be found in Scripture alone (sola scriptura). Some Protestants claim that any reliance upon tradition or magisterial authority is to place "manmade traditions" over and above "the Word of God," which is assumed to mean the Bible and nothing else. In response, Catholic apologists tend to focus on defending sacred Tradition and the Church's magisterial authority without going any deeper. But to adequately defend the three-pronged means by which divine revelation is passed on to Christians, we must first recognize the one who gives us that revelation: Jesus Christ, the Word of God (John 1:1), the God-Man who reveals the face of his Father in heaven (Matt. 11:27) by the power of the Holy Spirit (John 14:26).
If we are able to show that the revelation of God through Christ depends on persons more than it does on a book, then we'll show sola scriptura for what it truly is: a form of idolatry (cf. CCC 2113).