227. As a result of doctrine the Word not only becomes intelligible, but is a light to the understanding, for it resembles a lampstand with its lamps lit. Then a person sees more than he had seen before, and understands too things he had not previously understood. What is obscure and in disagreement he either does not see and passes over, or he sees and explains them so that they are in harmony with the doctrine. The experience of Christians is evidence that doctrine determines how the Word is viewed, and also how it is to be explained. All the Reformed churches view the Word in the light of their doctrine and this determines how they explain it; likewise the Roman Catholics view it in the light of their doctrine, and their explanation is determined by this. Even the Jews view it in the light of their doctrine, and their explanation is determined by this. Thus false doctrine produces false ideas, true doctrine true ideas. These facts show that true doctrine is like a lamp shining in the darkness, and like a sign-post on a road.