One trick Protestants use is selective quotation. For instance, they will quopte St. Athanasius, from Against the Heathen, saying, “:the sacred and inspired Scriptures are sufficient to declare the truth,” but ignore other writings by Athanasius such as this, from Ad Serapion: “But beyond these [Scriptural] sayings, let us look at the very tradition, teaching, and faith of the Catholic Church from the beginning, which the Lord gave, the Apostles preached, and the Fathers kept. Upon this the Church is founded, and he who should fall away from it would not be a Christian, and should no longer be so called.”
Note that the tradition he speaks of goes “beyond the Scriptures” yet is the norm and defining characteristic of a Christian.
Protestants also love to quote Acts 17:11: “Now these Jews [in Beroea] were more noble than those in Thessalonica, for they received the Word with eagerness, examining the scriptures daily to see if these things were so.” RSV. “See?”, Protestants exclaim triumphantly, “they examined the scriptures, not manmade traditions.” But wait…to see if what things were so? They had the scriptures already; what did they have to look at? Luke gives us the answer in 17:2,3, which tells how Paul’s custom in a new town was to go to the synagogue and argue from the scripture, that is, the Old Testament, that Jesus was the Christ. But the Jews in the synagogues had the scriptures also. What they did not have was the meaning, which had been hidden from the prophets of old, and revealed only after Christ had risen; that is, the tradition, the living faith, which Paul testified had been handed down to him as well. Just as the Ethiopian Eunuch in Acts 8 could read Isaiah all day and still not know who the suffering servant was, so the Jews in Beroea could not understand the scriptures until Paul went and “preached to them Jesus.” For the Scriptures by themselves need the interpretive context of Apostolic teaching passed down through the Church to reveal their meaning.
Read Sungenis’ book: there are pages of quotes from the Fathers supporting Tradition. Protestants forget that the Church came before the New Testament and passed down its meaning from the same Apostolic sources. Because they do not believe in Apostolic tradition, every mention of tradition to them means something merely human, and therefore suspect.