We find that true saints, or those persons who are sanctified by the Spirit of God, are in the New Testament called spiritual persons. And their being spiritual is spoken of as their peculiar character, and that wherein they are distinguished from those who are not sanctified. This is evident because those who are spiritual are set in opposition to natural men, and carnal men. Thus the spiritual man, and the natural man, are set in opposition one to another; I Corinthians 2:14–15, “The natural man receiveth not the things of the Spirit of God, for they are foolishness unto him; neither can he know them; because they are spiritually discerned. But he that is spiritual judgeth all things.” The Scripture explains itself to mean an ungodly man, or one that has no grace, by a natural man… That by carnal the Apostle means corrupt and unsanctified, is abundantly evident, by Romans 7:25 and Romans 8:1, 4–9, 12, 13; Galatians 5:16 to the end; Colossians 2:18. Now therefore, if by natural and carnal, in these texts, he intended “unsanctified”; then doubtless by spiritual, which is opposed thereto, is meant “sanctified” and gracious….
Now it may be observed that the epithet “spiritual,” in these and other parallel texts of the New Testament, is not used to signify any relation of persons or things to the spirit or soul of man, as the spiritual part of man, in opposition to the body, which is the material part: qualities are not said to be spiritual, because they have their seat in the soul, and not in the body: for there are some properties that the Scripture calls carnal or fleshly, which have their seat as much in the soul, as those properties that are called spiritual. Thus it is with pride and self-righteousness, and a man’s trusting to his own wisdom, which the Apostle calls fleshly (Colossians 2:18). Nor are things called spiritual, because they are conversant about those things that are immaterial, and not corporeal. For so was the wisdom of the wise men, and princes of this world, conversant about spirits, and immaterial beings; which yet the Apostle speaks of as natural men, totally ignorant of those things that are spiritual (I Corinthians, ch. 2). But it is with relation to the Holy Ghost, or Spirit of God, that persons or things are termed spiritual, in the New Testament. “Spirit,” as the word is used to signify the third person in the Trinity, is the substantive, of which is formed the adjective “spiritual,” in the holy Scriptures. Thus Christians are called spiritual persons, because they are born of the Spirit, and because of the indwelling and holy influences of the Spirit of God in them. And things are called spiritual as related to the Spirit of God; I Corinthians 2:13–14, “Which things also we speak, not in the words which man’s wisdom teacheth, but which the Holy Ghost teacheth, comparing spiritual things with spiritual. But the natural man receiveth not the things of the Spirit of God.” Here the Apostle himself expressly signifies, that by spiritual things, he means the things of the Spirit of God, and things which the Holy Ghost teacheth. The same is yet more abundantly apparent by viewing the whole context. Again, Romans 8:6, “To be carnally minded is death: but to be spiritually minded is life and peace.” The Apostle explains what he means by being carnally and spiritually minded, in what follows in the 9th verse, and shows that by being spiritually minded, he means a having the indwelling and holy influences of the Spirit of God in the heart. “But ye are not in the flesh, but in the Spirit, if so be the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his.”
Jonathan Edwards (1703-58), Religious Affections, 197-99.