5.1 [338] The blessed David reveals that the inability to control one’s tongue is the most shameful of diseases. For example, he even used to offer prayers about it, saying: “Place a guard on my mouth, O Lord, and a gate of constraint about my lips. Do not turn my heart away to words of wickedness.”1 In fact, I would say that it is priceless to make the wise choice of keeping one’s mind focused upon the thoughts that are appropriate for truly sensible people and, indeed, to use irreproachable speech in this endeavor. For it has been written that, “If a person does not stumble in his speech, he is a perfect man, capable of reining in the rest of his body too.”2 On the other hand, how could anyone not find fault, and quite understandably so, with someone using a carefree and relaxed tongue that has free rein to proceed to each and every [339] reprehensible thing?