When you speak, let every word be full and well rounded, every sentence clear and distinct, to the very last word. Many as they approach the end of a sentence lower the tone of the voice, speaking so indistinctly that the force of the thought is destroyed. Words that are worth speaking at all are worth speaking in a clear, distinct voice, with emphasis and expression. But never search for words that will give the impression that you are learned. The greater your simplicity, the better will your words be understood. GW 88.5
Young men and women, has God placed in your hearts a desire to do service for Him? Then by all means cultivate the voice to the utmost of your ability, so that you can make plain the precious truth to others. Do not fall into the habit of praying so indistinctly and in so low a tone that your prayers need an interpreter. Pray simply, but clearly and distinctly. To let the voice sink so low that it cannot be heard, is no evidence of humility. GW 89.1
To those who are planning to enter God's service as ministers, I would say, Strive with determination to be perfect in speech. Ask God to help you to accomplish this great object. When in the congregation you offer prayer, remember that you are addressing God, and that He desires you to speak so that all who are present can hear and can blend their supplications with yours. A prayer uttered so hurriedly that the words are jumbled together, is no honor to God and does the hearers no good. Let ministers and all who offer public prayer learn to pray in such a way that God will be glorified and the hearers will be blessed. Let them speak slowly and distinctly, and in tones loud enough to be heard by all, so that the people may unite in saying Amen.—Testimonies for the Church 6:380-383. GW 89.2
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Some of our most talented ministers are doing themselves great injury by their defective manner of speaking. While teaching the people their duty to obey God's moral law, they should not be found violating the laws of God in regard to health and life. Ministers should stand erect, and speak slowly, firmly, and distinctly, taking a full inspiration of air at every sentence, and throwing out the words by exercising the abdominal muscles. If they will observe this simple rule, giving attention to the laws of health in other respects, they may preserve their life and usefulness much longer than men in any other profession. The chest will become broader, and ...the speaker need seldom become hoarse, even by constant speaking. Instead of becoming consumptives, ministers may, by exercising care, overcome all tendency to consumption. GW 90.1
Unless ministers educate themselves to speak in accordance with physical law, they will sacrifice life, and many will mourn the loss of “those martyrs to the cause of truth;” when the facts in the case are, that by indulging in wrong habits, they did injustice to themselves and to the truth which they represented, and robbed God and the world of the service they might have rendered. God would have been pleased to have them live, but they slowly committed suicide. GW 90.2
The manner in which the truth is presented often has much to do in determining whether it will be accepted or rejected. All who labor in the great cause of reform should study to become efficient workmen, that they may accomplish the greatest possible amount of good, and not detract from the force of the truth by their own deficiencies. GW 90.3
Ministers and teachers should discipline themselves to articulate clearly and distinctly, allowing the full sound to every word. Those who talk rapidly, from the throat, jumbling the words together, and raising the voice to an unnaturally high pitch, soon become hoarse, and the words spoken lose half the force which they would have if spoken slowly, distinctly, and not so loud. They sympathies of the hearers are awakened for the speaker; for they know that he is doing violence to himself, and they fear that he will break down at any moment. It is no evidence that a man has zeal for God because he works himself up into a frenzy of excitement and gesticulation. “Bodily exercise,” says the apostle, “profiteth little.” [1 Timothy 4:8.] GW 91.1
The Saviour of the world would have His co-laborers represent Him; and the more closely a man walks with God, the more faultless will be his manner of address, his deportment, his attitude, and his gestures. Coarse and uncouth manners were never seen in our pattern, Christ Jesus. He was a representative of heaven, and His followers must be like Him. GW 91.2
Some reason that the Lord will by His Holy Spirit qualify a man to speak as He would have him; but the Lord does not propose to do the work that He has given man to do. He has given us reasoning powers, and opportunities to educate the mind and manners. And after we have done all we can for ourselves, making the best use of the advantages within our reach, then we may look to God with earnest prayer to do by His Spirit that which we cannot do for ourselves.—Testimonies for the Church 4:404, 405. GW 91.3