1 Corinthians 14:15 - Coke's Commentary on the Holy Bible

I will pray with the understanding also.— That is, according to Mr. Locke, "When moved to it by the Spirit, I will pray in an unknown tongue; but so that my meaning may be understood by others;" that is to say, "I will not do it but when there is some one by to interpret." I will not pretend, says Mr. Locke, to justify this interpretation of the term τω νοι by the exact rules of the Greek idiom; but the sense of the place will, I think, bear me out in it; and he must be little conversant with the writings of St. Paul who does not observe, that when he has used a term, he is apt to repeat it again in the same discourse, in a way peculiar to himself, and somewhat varied from its ordinary signification. So, having here in the foregoing verse used the word νους, for the sentiment of his own mind, which was unprofitable for others when he prayed in a tongue unknown to them, and opposed it to the word πνευμα, which he used there for his own sense, accompanying his own words, intelligible to himself, when by the impulse of the spirit he prayed in a foreign tongue; he continues in this verse to use praying with the Spirit, and with the understanding in the same opposition, the one for praying in a strange tongue, which alone his own mind understood and accompanied; the other, for praying so, as that the meaning of his mind in those words which he uttered was made known to others, so that they were also benefited. Dr. Doddridge, however, is of opinion, that the sense and high spirit of the Apostle in this clause is lost by the above interpretation. I apprehend, says he, it is designed further to intimate what a want of manly sense and right understanding it must betray, to talk in a language which the hearers could not comprehend, how sublime soever the discourse may be. This the 20th verse, and especially the use of the word τελειοι, there strongly suggests. Instead of, I will pray with the understanding, and I will sing with the understanding, Dr. Heylin reads, But my prayer shall be intelligible;—but my hymn shall be intelligible.