1 Corinthians 14:9

“So likewise you, unless ye utter by the tongue words easy to be understood, etc.] This is an accommodation of the foregoing similes to the case in hand: for as unless there is a distinction of notes and tunes, it cannot be music, nor it cannot be known what is piped or harped; and unless the trumpet gives a certain sound, none can know when to prepare himself for the battle; so unless in the public ministry and service a language is spoken, and words made use of, which are understood without difficulty: how shall it be known what is spoken? the subject matter of the discourse, prayer, or psalm, will be all lost, and therefore cannot be for edification, exhortation, or comfort: for ye shall…”

“So . . . ye--who have life; as opposed to "things without life" (Co1 14:7). by the tongue--the language which ye speak in. ye shall speak--Ye will be speaking into the air, that is, in vain (Co1 9:26).”

“So likewise ye ... - To apply the case. If you use a foreign language, how shall it be known what is said, or of what use will it be, unless it is made intelligible by interpretation? Utter by the tongue - Unless you speak. Words easy to be understood - Significant words (margin), words to which your auditors are accustomed. For ye shall speak into the air - You will not speak so as to be understood; and it will be just the same as if no one was present, and you spoke to the air. We have a proverb that resembles this: “You may as well speak to the winds:” that is, you speak where it would not be understood, or where the words would have no effect. It may he observed here, that the practice…”

“Unless ye utter by the tongue - Which is miraculously given you. Words easy to be understood - By your hearers. Ye will speak to the air - A proverbial expression. Will utterly lose your labour. 1 Corinthians 14:11”

“easy: Gr. significant, Co1 14:19 for: Co1 9:26 1 Corinthians 14:11”