"indistinct way, their utterance may be clear, forcible, and edifying. Do not let the voice fall after each word, but keep it up so that each sentence will be full and complete. Will it be worth disciplining yourself, if by so doing you are able to add interest to the service of God and to edify His children? The voice of thanksgiving, praise, and rejoicing is heard in heaven. The voices of the angels in heaven unite with the voices of the children of God on earth as they ascribe honor and glory and praise to God and to the Lamb for the great salvation provided. CT 246.1 Let everyone seek to do his best. Let those who have enlisted under the banner of Prince Immanuel grow daily in grace and efficiency. Let the teachers in our institutions endeavor so to train their students in all lines of education that they may come forth properly disciplined to bless mankind and to glorify God. CT 246.2"
"How is it then, brethren? when ye come together, every one of you hath a psalm, hath a doctrine, hath a tongue, hath a revelation, hath an interpretation. Let all things be done unto edifying."
Both passages emphasize the importance of edifying others through speech and participation in religious services. 1 Corinthians 14:26 speaks to the variety of contributions, while EGW focuses on the quality of voice and its impact on edification.
"It is essential that students be trained to read in a clear, distinct tone. We have been pained as we have attended conference meetings, tract society meetings, and meetings of various kinds, where reports were read in an almost inaudible voice or in a hesitating manner or a muffled tone. One half the interest in a meeting is killed when the participants do their part in an indifferent, spiritless fashion. They should learn to speak in such a way that they can edify those who listen. Let everyone connected with missionary work qualify himself to speak in a clear, attractive way, enunciating his words perfectly. CT 246.3"
"So likewise ye, except ye utter by the tongue words easy to be understood, how shall it be known what is spoken? for ye shall speak into the air."
Both passages directly address the need for clear and understandable speech in order to effectively communicate and edify listeners. EGW's emphasis on clear enunciation directly reflects the principle in 1 Corinthians 14:9.