For if I pray in an unknown tongue, my spirit prays, but my understanding is unfruitful.
For he that speaks in an unknown tongue speaks not unto men, but unto God: for no man understands him; but in the spirit he speaks mysteries.
Yet in the church I had rather speak five words with my understanding, that by my voice I might teach others also, than ten thousand words in an unknown tongue.
Therefore let him that speaks in an unknown tongue pray that he may interpret.