“You may give thanks
But the other man
Is not edified.”
σὺ μὲν γὰρ καλῶς εὐχαριστεῖς, ἀλλ’ ὁ ἕτερος οὐκ οἰκοδομεῖται.
Paul said that you may give thanks well enough (σὺ μὲν γὰρ καλῶς εὐχαριστεῖς), but the other man is not edified (ἀλλ’ ὁ ἕτερος οὐκ οἰκοδομεῖται). Paul explained that there was nothing wrong with the person praising or thanking God in tongues, but the other people there would not be edified or built up. They would be perplexed. Personally, there was nothing wrong, but the community did not progress based on the individual speaking in tongues. Speaking in tongues was a good personal activity, but it did not help the community of believers. Do you know anyone who speaks in tongues?