1 Corinthians 14:11
King James Version
“Therefore if I know not the meaning of the voice, I shall be unto him that speaketh a barbarian, and he that speaketh a barbarian unto me.”
Context
8For if the trumpet give an uncertain sound, who shall prepare himself to the battle?
9So 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.
10There are, it may be, so many kinds of voices in the world, and none of them without signification.
11Therefore if I know not the meaning of the voice, I shall be unto him that speaketh a barbarian, and he that speaketh a barbarian unto me.
12Even so ye, forasmuch as ye are zealous of spiritual seek that ye may excel to the edifying of the church.
13Wherefore let him that speaketh in an tongue pray that he may interpret.
14For if I pray in an tongue, my spirit prayeth, but my understanding is unfruitful.