They speak according to the word or no light in them

Isaiah 8:20 To the law and to the testimony: If they speak not according to this word, It is because there is no light in them.

If you hear a preacher who has no respect for the Word of God then you should have no respect for him. Those that would make light of the Bible show that there is no light in them. Those that would doubt the Bible should be doubted. I want to preach the word of God, the law and testimony. I want to speak according to the word. If I do not speak according to the word then I lose all authority.