This is where Paul's illustrations land. Just as no one can know a tune or a battle call without clear sounds, no one can know what a speaker means without words they understand. Barnes explains "words easy to be understood" as "words to which your auditors are accustomed." Paul asks the question so the Corinthians will apply the logic to their own meetings, where uninterpreted tongues left hearers with nothing. His closing phrase, "ye shall speak into the air," shows what such speech accomplishes for others: nothing.

Paul answers his own question in the same verse: "for ye shall speak into the air" (1 Corinthians 14:9). He goes on to say that if he does not know the meaning of a voice, speaker and hearer are each "a barbarian" to the other (1 Corinthians 14:11). So he urges, "seek that ye may excel to the edifying of the church," and tells the one who speaks in a tongue to "pray that he may interpret" (1 Corinthians 14:12-13).

Barnes compares "speak into the air" to the proverb "You may as well speak to the winds." Gill describes such speech as "beating the air, and talking to the wind." Both commentators also apply the verse to their own day: Barnes says "All preaching should be plain, simple, perspicuous, and adapted to the capacity of the hearers," and Gill warns against "great swelling words of vanity" in public speaking. Perspicuous means clear and easy to follow.

Paul's concern is not technique but the good of others. A chapter earlier he wrote that love "seeketh not her own" (1 Corinthians 13:5), and the same concern shows here in speech. Words that only the speaker understands serve the speaker. Words "easy to be understood" serve the church.

God's gifts are meant to pass from one person to another. When they stop at the speaker's lips, Paul says, they go "into the air." When they are understood, the church is built up, which is the purpose Paul keeps returning to throughout 1 Corinthians 14 (1 Corinthians 14:3-5, 12, 26).