Overview
Sola scriptura is one of the five solas, considered by some Protestant groups to be the theological pillars of the Reformation. The key implication of the principle is that interpretations and applications of the Scriptures do not have the same authority as the Scriptures themselves; hence, the ecclesiastical authority is viewed as subject to correction by the Scriptures, even by an individual member of the Church.
Luther said, "a simple layman armed with Scripture is greater than the mightiest pope without it". The intention of the Reformation was to correct the perceived errors of the Catholic Church by appeal to the uniqueness of the Bible's authority and to reject what Catholics considered to be Apostolic Tradition as a source of original authority alongside the Bible, wherever Tradition did not have biblical support or where it supposedly contradicted Scripture.
Sola scriptura, however, does not ignore Christian history and tradition when seeking to understand the Bible. Rather, it sees the Bible as the only final authority in matters of faith and practice. As Martin Luther said, "The true rule is this: God's Word shall establish articles of faith, and no one else, not even an angel can do so."
The term heretical is commonly used by Protestants who denounce teachings and institutions that they accordingly view as deviating from Scripture.
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