For it usually turns out that even someone who is not a Christian knows something about the earth, the sky, and the other elements of this world; about the movement and revolution, or even the magnitude and positions of the stars; about the known eclipses of the sun and moon; about the cycles of years and seasons; about the properties of animals, bushes, minerals, and other things of the sort. He knows these things, and holds them as quite certain through reason or experience.
So it is terribly inappropriate and destructive and a thing to be avoided at all costs, that someone should hear a Christian speaking of these things as if he were speaking according to the Christian writings, so that the people who hear him raving like that can hardly keep themselves from laughing.
The worst part is not that someone who is wrong should be laughed at, but that outsiders should believe that our authors think those things, and rebuke and reject them as ignorant—with great destruction of those whose salvation is our business.