But whoso looketh into the perfect law of liberty,.... By which is meant, not the moral law, but the Gospel; for only of that is the apostle speaking in the context: this is no other than the word of truth, with which God begets men of his own will; and is the ingrafted word which is able to save, and of which men should be doers, as well as hearers, Jas 1:18, and this is compared to a glass by the Apostle Paul, 2Co 3:18, and the word here used for looking into it is the same word the Apostle Peter uses of the angels, who desired to look into the mysteries of the Gospel, 1Pe 1:12 all which serve to strengthen this sense; now the Gospel is called a law; not that it is a law, strictly speaking, consisting precepts, and established and enforced by sanctions penalties; for it is a declaration of righteousness and salvation by Christ; a publication of peace and pardon by him; and a free promise of eternal life, through him; but as it is an instruction, or doctrine: the law with the Jews is called hrwt, because it is teaching and instructive; and everything that is so is by them called by this name: hence we find the doctrine of the Messiah, which is no other than the Gospel, is in the Old Testament called the law of the Lord, and his law, Isa 2:2 and in the New Testament it is called the law, or doctrine of faith, Ro 3:27 and this doctrine is perfect, as in Ps 19:7, it being a perfect plan of truths, containing in it all truth, as it is in Jesus, even all the treasures of wisdom and knowledge; and because it is a revelation of things perfect; of the perfect righteousness of Christ, and of perfect justification by it, and of free and full pardon of sins through him, and of complete salvation by him; and because it directs to Christ, in whom perfection is: and it is a law or doctrine of liberty;ton thv eleuyhriav, "that which is if liberty"; which has liberty for its subject, which treats of it, even of the liberty wherewith Christ makes his people free: the Gospel proclaims this liberty to captive souls; and is the word of truth, which makes them free, or is the means of freeing them from the slavery of sin, from the captivity of Satan, and from the bondage of the law; and is what gives souls freedom and boldness at the throne of grace; and is that which leads them into the liberty of grace here, and gives them a view and hope of the glorious liberty of the children of God hereafter.
This doctrine is as a glass to look into; in which is beheld the glory of Christ's person and office, and grace; and though by the law is the knowledge of sin, yet a man never so fully and clearly discovers the sin that dwells in him, and the swarms of corruption which are in his heart, as when the light of the glorious Gospel shines into him, and when in it he beholds the beauty and glory of Jesus Christ; see Isa 6:5 and looking into this glass, or into this doctrine, is by faith, and with the eyes of the understanding, opened and enlightened by the Spirit of God; and the word here used signifies a looking wistly and intently, with great care and thought, and not in a slight and superficial manner; and such a looking is designed, as is attended with effect; such an one as transforms into the same image that is beheld, from glory to glory; and happy is the man that so looks into it.
And continueth therein; is not moved away from the hope of the Gospel, nor carried about with divers and strange doctrines; but is established in the faith, stands fast in it, and abides by it; or continues looking into this glass, and to Christ, the author and finisher of faith, who is beheld in it; and keeps his eye upon it, and the object held forth in it; and constantly attends the ministration of it:he being not a forgetful hearer; but takes heed to the things he hears and sees, lest he should let them slip; and being conscious of the weakness of his memory, implores the divine Spirit to be his remembrancer, and bring to his mind, with fresh power and light, what he has heard:but a doer of the work; of the work of faith, and labour of love, and patience of hope, and of every work and ordinance the Gospel ministry points unto; doing and being subject to all in faith, from a principle of love, and with a view to the glory of God and Christ.