"***** The Test of N ew Light Our brethren should be willing to investigate in a candid way every point of controversy. 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 it. We are all under obligation to God to know what He sends 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 .] If the light presented meets this test, we are not to refuse to accept it because it does not agree with our ideas. GW 300"
"To the law and to the testimony: if they speak not according to this word, it is because there is no light in them."
Ellen White directly references Isaiah 8:20 in this passage.