When the Word of God is not set up as the supreme authority, division is inevitable. Such happens even in evangelical churches, when pastors and other leaders begin substituting their own ideas for the truths of Scripture. The substitution is seldom intentional, but it will always happen when the Bible is neglected. A Bible that is not studied carefully cannot be followed carefully. And where it is not followed there will be division, because there will be no common ground for beliefs and practices. When the truth of Scripture is not the sole authority, men's varied opinions become the authority.