This is why we KNOW that Sacred Scripture is above and in authority over any so-called Traditions of the church. It's amazing how frequently we must defend the concept of sola Scriptura on these threads. For some reason, a few presume that belief means EVERYTHING must be in the Bible specifically or it cannot be accepted and they insist that their "Church" teachings and its traditions are equal in authority to God's word. But what the earliest Christians believed and taught was that Scripture ALONE is the authority by which all other teachings of the faith must be measured against.
We can be assured that the "whole counsel of God" has been declared (Acts 20:27) through His word and the truths that have been revealed to us are trustworthy and complete. What happens is that our understanding of them grows and matures over time but they remain THE authority by which we are all called to obey and be in subjection to.
I believe that all doctrinal truth has been laid down by God in Holy Scripture. I do not believe, though, that He is done speaking to us. He has many things to say to us. He is in a vital and living relationship with us. He is alive! He isn’t just recorded doctrine. Doctrine is of paramount importance, and The LORD will never contradict it, nor add to it. The LORD is our Father and loves us more than we will ever know. He is very interested in communicating with us.
I know you didn’t say else wise, but many fundamentalist take great importance in believing that when The Bible was finished God stopped speaking to us, except directly through His written Word. The Word is meant to lead us into a living, intimate and vital relationship with Him. The Word teaches us who He is, and also His truths, as guides in our lives, as to what we are to wrap our hearts around and live according to. As Jesus said it isn’t in itself going to give us life. For that we must come to Him. Coming to Him is what we are do our entire lives, on a continuous basis. When we come to Him, I believe, it is His desire to communicate with us about many things, in different ways, but as long as so many of us refuse to believe so we are not opened to hearing Him.