In a July 8, 1530 letter from Martin Luther to Lazarus Spengler, Luther interprets his seal: Grace and peace from the Lord. As you desire to know whether my painted seal, which you sent to me, has hit the mark, I shall answer most amiably and tell you my original thoughts and reason about why my seal is a symbol of my theology. The first should be a black cross in a heart, which retains its natural color, so that I myself would be reminded that faith in the Crucified saves us. "For one who believes from the heart will be justified" (Romans 10:10). Although it is indeed a black cross, which mortifies and which should also cause pain, it leaves the heart in its natural color. It does not corrupt nature, that is, it does not kill but keeps alive. "The just shall live by faith" (Romans 1:17) but by faith in the crucified. Such a heart should stand in the middle of a white rose, to show that faith gives joy, comfort, and peace. In other words, it places the believer int...