John Gill emphasizes the importance of living righteously as a reflection of true faith in Christ, warning against the deception of believing that knowledge alone is sufficient for salvation. He explains that righteousness is not achieved through one's own works or adherence to the law, but through faith in the righteousness of Christ, which is imputed to believers. Gill asserts that true righteousness is demonstrated through a life of holiness and good works, which serve as evidence of one's faith and alignment with Christ's character. He encourages believers to renounce their own insufficient righteousness and to embrace the righteousness of Christ, which leads to a transformed life. Ultimately, Gill highlights that while good works do not make one righteous, they are the fruit that reveals a person's true standing before God.

Ver. 7. Little children, let no man deceive you,.... Neither by these doctrines, nor by wicked practices, drawing into the belief of the one, or into the performance of the other; suggesting, as the Gnostics did, that knowledge without practice was enough, and that it was no matter how a man lived, provided his notions of the Gospel were right: he that doeth righteousness, is righteous; not that any man is made righteous by the works of the law, or by his obedience to the law of works, for this is contrary to the express word of God; and besides, the best righteousness of man is imperfect, and can never constitute or denominate him righteous before God; and was he justified by it; it would not only lay a foundation for boasting in him, which ought not to be, but would make the death, the sacrifice, and righteousness of Christ, to be in vain; men are only made righteous by the righteousness of Christ, which be has wrought out which is revealed in the Gospel, and received by faith, and which God imputes without works; so that he that doeth righteousness is he that being convinced of the insufficiency of his own righteousness, and of the excellency and suitableness of Christ's righteousness, renounces his own, and submits to his; who lays hold upon it, receives it, and exercises faith on it, as his justifying righteousness; and, in consequence of this, lives in a course of holiness and righteousness, in opposition to, and distinction from one that commits sin, or lives a sinful course of life; which, though it does not make him righteous in the sight of God, yet it shows him to be righteous in the sight of men, and proves that faith to be right which lays hold on the righteousness of Christ, by which he is truly righteous: even as he is righteous; as Christ himself is righteous; and so the Syriac version reads; not as personal, or as he is personally and essentially righteous as God; but as mystical, every member of his body being clothed with the same robe of righteousness the whole body of Christ is, and indeed justified by the same righteousness that he as Mediator was, when he rose from the dead, as the representative of his people: moreover, as Christ showed himself to be righteous as man, by doing good, so believers in him, by imitating him, and walking as he walked, show themselves to be good and righteous, like, though not equal to him; for as a tree is known by its fruits, so is a good man by his good works, and a righteous man by doing righteousness; and as good fruit does not make a good tree, but shows it to be good, so good works do not make a good man, nor a man's own righteousness make him a righteous man, but show him to be so.