If a brother is teaching error, those who are in responsible positions ought to know it; and if he is teaching truth, they ought to take their stand at his side. We should all know what is being taught among us, for if it is truth, we need to know it. The Sabbath school teacher needs to know it, and every Sabbath school scholar ought to understand it. We are all under obligation to God to know what He sends to us. He has given directions by which we may test every doctrine—“To the law and to the testimony: if they speak not according to this word, it is because there is no light in them” (Isaiah 8:20). But if it is according to this test, do not be so full of prejudice that you cannot acknowledge a point when it is proved to you, simply because it does not agree with your ideas. (TDG 93.3) MC VC

To the law and to the testimony: if they speak not according to this word, it is because there is no light in them. Isaiah 8:20. (TDG 355.1) MC VC