1 Corinthians 14:8 (KJV)

But he that prophesieth speaketh unto men to edification, and exhortation, and comfort.

He that speaketh in an unknown tongue edifieth himself; but he that prophesieth edifieth the church.

I would that ye all spake with tongues but rather that ye prophesied: for greater is he that prophesieth than he that speaketh with tongues, except he interpret, that the church may receive edifying.

Now, brethren, if I come unto you speaking with tongues, what shall I profit you, except I shall speak to you either by revelation, or by knowledge, or by prophesying, or by doctrine?

And even things without life giving sound, whether pipe or harp, except they give a distinction in the sounds, how shall it be known what is piped or harped?

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.

There are, it may be, so many kinds of voices in the world, and none of them is without signification.

Therefore if I know not the meaning of the voice, I shall be unto him that speaketh a barbarian, and he that speaketh shall be a barbarian unto me.

Even so ye, forasmuch as ye are zealous of spiritual gifts, seek that ye may excel to the edifying of the church.

Wherefore let him that speaketh in an unknown tongue pray that he may interpret.