Pulpit Commentary
Verse 17. Now the Lord is that Spirit. The "but" (Authorized Version, "now") introduces an explanation. To whom shall they turn? To the Lord. "But the Lord is the Spirit." The word "spirit" could not be introduced thus abruptly and vaguely; it must refer to something already said, and therefore to the last mention of the word "spirit" in ver. 3. The Lord is the Spirit, who giveth life and freedom, in antithesis to the spirit of death and legal bondage (see ver. 6; and comp. 1 Corinthians 15:45). The best comment on the verse is Romans 8:2, "For the law of the spirit of life in Christ Jesus hath made me free from the law of sin and death." All life and all religion had become to St. Paul a vision of all things in Christ. He has just said that the spirit giveth life, and, after the digression about the moral blindness which prevented the Jews from being emancipated from the bondage of the letter, it was quite natural for him to add, "Now the Lord is the Spirit to which I alluded." The connection in which the verse stands excludes a host of untenable meanings which have been attached to it. There is liberty. The liberty of confidence (ver. 4), and of frank speech (ver. 12), and of sonship (Galatians 4:6, 7), and of freedom from guilt (John 8:36); so that the Law itself, obeyed no longer in the mere letter but also in the spirit, becomes a royal law of liberty, and not a yoke which gendereth to bondage (James 1:25; James 2:12) a service, indeed, but one which is perfect freedom (Romans 5:121; 1 Peter 2:16).