Scripture itself promises that the Spirit will guide Christ's disciples into all truth. And that the church itself is the pillar and foundation of the truth. Of course Christ is the Cornerstone, the one on whom our faith is founded. The church was involved in that founding from Christ by the Spirit. The apostles and prophets receiving from God for us this faith that is ours in Jesus. And the church continues to be the entity/body in which we are to learn and grow in the Lord.
When I hear someone say tradition and interpretation don't matter; it's the Bible that is the word of God, I wince a bit. Whenever we read any of Scripture there is always a combination of interpretation and tradition occuring. Unless we're just doing so as an individual with our own interpretation. But that is not God's intention.
We can think we're reading the Bible for ourselves, and that is important. But we little realize just how much tradition and interpretation are present in our reading of it. Even in the translation of Scripture from the Greek, Hebrew and Aramaic, there is invariably interpretation going on. True in the most "literal" translation, if it really is a translation. Because the translator is trying to get to the meaning of a manuscript in one language and put it in the closest parallel meaning of another language.
We all need to read the Bible, God's word for ourselves. The Spirit can help us in our own private reading if we do so prayerfully with the desire to know God more and God's will for us in Jesus. But we must not imagine that tradition either should not or does not impact us. It does. Nor should we think we're not interpreting as we read. Indeed we are. To think otherwise has resulted in people promoting errors from not reading Scripture well, and in context. And it has also resulted in unnecessary divisions among us Christians. That is not to say there aren't divisions that had a good reason for occuring at their start. But properly speaking such divisions must not cause us to be aloof from other true Christian churches and people. There is, after all only one body along with our one faith.
With our inevitable differences in interpreting matters that while important are not crucial for us being in the faith, let us seek to emphasize what is essential. In that we need unity in the faith. In nonessentials liberty. And in all things, love (from the words of Augustine).
What might you like to add to this a bit heavy theological post?