1 Corinthians 14:14
For if I pray in a foreign language, my spirit prays but my mind is not productive.
1 Corinthians 14:2
For the person who speaks in a foreign language is not actually speaking to people but to God. Indeed, no one understands him, because he is talking about secrets by the Spirit.
1 Corinthians 14:15-16
What does this mean? I will pray with my spirit, but I will also pray with my mind. I will sing psalms with my spirit, but I will also sing psalms with my mind.
1 Corinthians 14:19
But in church I would rather speak five words with my mind to instruct others than 10,000 words in a foreign language.