If you are a protestant, do you know the five solas? It says, Christians are saved by grace alone, through faith alone, in Christ alone, as revealed by Scripture alone, to the glory of God alone.
Out of these, Sola scriptura is often referred to as the formal principle of the Reformation - for all other doctrines are understood from the Scriptures, and the main disagreement with the Catholic church was pertaining to practices that Martin Luther found to be outside the Scriptures and even contradictory to them. Sola scriptura means only Scripture. Because Scripture is God-breathed, it is considered sufficient, authoritative, and true - for the faith and practice of the Christian. “All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness” (2 Timothy 3:16). Of course, God continues to speak through church elders, and saints, many of which are recorded in several books and traditions throughout history. Yet, the authority of those teachings is limited in comparison to the scriptures.
Let's look at the following questions. Expand to know more about the question of your interest. Just some disclaimers before you read the rest of the article: (i) There is so much to read pertaining to this, that as I read, most of what I believe is affirmed, and where I lack, I do grow. So, there is always some scope for change. (ii) I don't necessarily subscribe to all the views of the links that I've referred to and cited in this article.
Yet, I think these are very important topics that we should think about and discuss! Feel free to disagree or comment.
Does Bible teach the principle of sola scriptura?
Why is sola scriptura important?
What do we mean by Inspiration - with regard to the Bible?
What do we mean by Inerrancy and Infallibility - with regard to the Bible?
What about the reliability of the Bible?
Who decided what is Scripture? Timeline on how we got our Bible
What are the different translations all about?