I've always enjoyed this charming little story about Martin Luther. He dearly loved his wife Katie and was devoted to her, but it seems he had to struggle all the time with her dreadful habit of worry. Once when he was traveling, he wrote her this letter, "To the saintly, worrying Lady Katherine Luther, doctor at Zulsdorf and Wittenberg, my gracious, dear wife. We thank you heartily for being so worried that you can't sleep, for since you started worrying about us, a fire broke out near my door, and yesterday, no doubt due to your worry, a big stone, save for the dear angels, would have fallen and crushed us like a mouse in a trap. If you don't stop worrying, I'm afraid the earth will swallow us. Pray and let God worry. Cast your burden on the Lord."