1 Corinthians 14:2 in the King James Version
For he that speaketh in an unknown tongue speaketh not unto men, but unto God: for no man understandeth him; howbeit in the spirit he speaketh mysteries.
Context
1 Follow after love and earnestly desire spiritual gifts, but especially that you may prophesy.
2 For he who speaks in another language speaks not to men, but to God, for no one understands, but in the Spirit he speaks mysteries.
3 But he who prophesies speaks to men for their edification, exhortation, and consolation.