John Gill's Bible Commentary Ver. 2. For he that speaketh in an unknown tongue , etc.] Or with tongues, as some copies and the Ethiopic version read: Dr. Lightfoot thinks, that the Hebrew tongue, which was become a dead language, and understood but by few, is here meant, and that not without reason; seeing the public prayers, preaching, and singing of psalms among the Jews, were in this languages f284 ; in imitation of whom, such ministers, who had the gift of speaking this language, read the Scriptures, preached, prayed, and sung psalms in it, which were no ways to the edification of the people, who understood it not; upon which account the apostle recommends prophesying, praying, and singing, in a language that was understood: otherwise he speaketh not unto men ; to the understanding, profit, and edification of men: but unto God: to his praise and glory, and he only knowing, who knows all languages, and every word in the tongue what is said; excepting himself, unless there should be any present capable of interpreting: for no man understandeth him : or heareth him: that is, hears him, so as to understand him; he may hear a sound, but he cannot tell the meaning of it, and so it is of no use and advantage to him: howbeit in the Spirit he speaketh mysteries ; though under the influence and by the extraordinary gift of the Spirit he has, and to his own Spirit and understanding, and with great affection and devotion within himself, he speaks of the deep things of God, and the mysteries of his grace, the most glorious truths of the Gospel, yet the meaning of his voice and words not being known, he is a barbarian to them that hear him; and though what he delivers are truths of the greatest importance, they are a mere jargon to others, being unintelligible.
Matthew Henry Commentary
Verses 1-5 - Prophesying, that is, explaining Scripture, is compared with speakin with tongues. This drew attention, more than the plain interpretatio of Scripture; it gratified pride more, but promoted the purposes of Christian charity less; it would not equally do good to the souls of men. What cannot be understood, never can edify. No advantage can be reaped from the most excellent discourses, if delivered in languag such as the hearers cannot speak or understand. Every ability of possession is valuable in proportion to its usefulness. Even fervent spiritual affection must be governed by the exercise of the understanding, else men will disgrace the truths they profess to promote.
Greek Textus Receptus
ο 3588 T-NSM γαρ 1063 CONJ λαλων 2980 5723 V-PAP-NSM γλωσση 1100 N-DSF ουκ 3756 PRT-N ανθρωποις 444 N-DPM λαλει 2980 5719 V-PAI-3S αλλα 235 CONJ τω 3588 T-DSM θεω 2316 N-DSM ουδεις 3762 A-NSM γαρ 1063 CONJ ακουει 191 5719 V-PAI-3S πνευματι 4151 N-DSN δε 1161 CONJ λαλει 2980 5719 V-PAI-3S μυστηρια 3466 N-APN
Robertson's NT Word Studies
14:2 {For no man understandeth} (oudeis gar akouei). Literally, hears, gets the sense, understands. Verb akouw used either of hearing the sound only or getting the idea (cf. #Ac 9:7; 22:9). {Mysteries} (musteria). Unexplained mysteries (#1Co 2:7).