Isaiah 48:17

Thus saith the Lord, thy Redeemer
A character peculiar to Christ, who engaged in covenant to be the Redeemer of his people; was promised and prophesied of as such; and who came into this world for this purpose, and has obtained eternal redemption: the Holy One of Israel;
who came of Israel as man, and as such was holy, and without any spot or stain of sin and who, as God, is the most holy, in his nature and works; and, as Mediator, the Sanctifier of Israel, and is in the midst of them as such: I am the Lord thy God;
and so fit to be the Redeemer and Sanctifier of them; and happy are those who can say with Thomas, "my Lord and my God"; and who further describes himself, and declares his work and office: which teacheth thee to profit;
or "teacheth thee profitable things" {p}; as the whole of the Gospel ministry is, whether it respects doctrines relating to the knowledge of the Persons in the Godhead; the knowledge of God in Christ; the person and offices of Christ; and the person and operations of the Spirit: or to the knowledge of man; his lost and depraved state; having sinned in Adam, the guilt of his sin is imputed to him, and a corrupt nature propagated; the bias of the mind being to evil, and man impotent to all that is good: or to the way of salvation by the grace of God, as the fruit and effect of the love of God; the doctrines of his eternal love, and of redemption by Christ; of justification by his righteousness; pardon by his blood; atonement by his sacrifice; regeneration by his Spirit and grace; and of the perseverance of the saints in faith and holiness. These are profitable doctrines, which serve to display the riches of divine grace, make for the glory of the Redeemer, and the good of souls, their peace, joy, comfort, and salvation. These are the wholesome words of our Lord Jesus. Or whether these teachings respect ordinances which Christ has appointed, and in his word and by his Spirit teaches men to observe; and which are profitable to lead to him, are breasts of consolation from him, and the means of spiritual strength: or whether they regard the duties of religion, the performance of good works; which, though not profitable to God, and not meritorious of anything from him, yet are profitable to men; to others by way of example, and otherwise, and to the doers of them, who find pleasure, peace, and advantage, by them. Christ was a teacher of these things when on earth, and he still teaches them by his ministers, whom he commissions and qualifies, and by his Spirit accompanying their ministrations: which leadeth thee by the way that thou shouldest go;
Christ leads his people out of the wrong way, in which they naturally are, into the right way; to himself, as the way to the Father, and as the way of salvation, and unto eternal life; he takes them by the hand, and teaches them to go in the path of faith, and to walk in him by it; he leads them in the ways of truth and righteousness, in the highway of holiness, in the path of duty; and, though in a rough way of afflictions, yet in a right way to heaven and happiness.