1 Corinthians 14:9

14:9 So also you, unless you uttered by the tongue words easy to understand, how would it be known what is spoken? For you would be speaking into the air.
-World English Bible

Other Translation

14:9 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.
-King James Version