1 Corinthians 14:9

The Scriptures 1998

So also you, if you do not give speech by the tongue that is clear, how shall it be known what is spoken? For you shall be speaking into the air.

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There are, undoubtedly, so many kinds of sounds in the world, and none of them is without distinct sound.

Therefore I run accordingly, not with uncertainty. Thus I fight, not as one who beats the air.