54. The Word by means of doctrine is not only understood, but it also as it were gives light; because without doctrine it is not understood, and it is like a lampstand without a light, as was shown above. The Word, therefore, by means of doctrine is understood, and is like a lampstand with its lamp lit. Man then sees more things than he had seen before, and he also understands those things which he had not understood before. Things obscure and out of agreement he either does not notice and passes over, or he sees and explains them as in agreement with doctrine. The experience of the Christian world testifies that the Word is understood from doctrine, and also that it is explained according to doctrine. For all the Reformers see the Word from their own doctrine and they explain the Word according to it; so too the Roman Catholics see it from their doctrine and they explain it accordingly; and even the Jews do likewise; thus falsities are seen from false doctrine, and truths from true doctrine. Hence it is evident that true doctrine is like a lamp in darkness and a sign-post on the way.
Doctrine, however, must not only be taken from the sense of the Letter of the Word, but it must also be confirmed by that sense. For if not confirmed by it, the truth of doctrine appears as if it were only man's intelligence in it and not the Lord's Divine Wisdom; and thus doctrine would be like a house in the air, and not on the ground, and consequently without a foundation.