Isaiah 55:3

Incline your ear, and come unto me
The exhortations are repeated, to show the importance of them, how welcome these persons were to the Lord, and to his house, and his earnest and tender care and concern for them: hear, and your soul shall live;
or, "that your soul may live ^F6"; spiritually and eternally. There must be life before hearing; men must be made alive before they can come to Christ spiritually, or hear his word so as to have a spiritual understanding of it, or savingly believe it; but the meaning is, that by coming and hearing the word of the Lord, they should have something to live upon, good, solid, substantial food; and that they should live comfortably and plentifully, and that for ever. It was reckoned a great absurdity in Sunlungus, a Chinese philosopher, who asserted ^F7 that a man had three ears, one different from the two that are seen; it is true in a spiritual sense. And I will make an everlasting covenant with you;
which is to be understood not of the covenant of works, nor of the covenant of circumcision, nor of the Sinai covenant; but of the covenant of grace, which is an "everlasting one"; it is from everlasting, being founded in the everlasting love of God, is according to his eternal purposes; Christ is the Mediator of it, who as such was set up from everlasting, and the promises and blessings of it were so early put into his hands; and it will continue to everlasting, sure, firm, unalterable, and immovable. This, properly speaking, was made with Christ from all eternity, and his people in him; it is made manifest to them at conversion, when they are shown it, and their interest in it; when God makes himself known to them as their covenant God, and Christ as the Mediator of it is revealed to them; when the Lord puts his Spirit into them, and makes them partakers of the grace of it; shows them their interest in the blessings of it, and opens and applies the promises of it unto them; and these are made manifest in the ministration of the Gospel, and in the administration of ordinances: even "the sure mercies of David"; that is, the Messiah, the son of David, and his antitype, whence he is often called by his name, ( Ezekiel 34:23 Ezekiel 34:24 ) ( Ezekiel 37:24 Ezekiel 37:25 ) ( Hosea 3:5 ) , and so Aben Ezra, Kimchi, and others ^F8, interpret it. The blessings of the covenant are called "mercies", because they spring from the mercy of God, as redemption, pardon of sin, regeneration, salvation, and eternal life; and they are the mercies of David, or of Christ, for the promises of them were made to him, and the things themselves put into his hands, and are ratified and confirmed by his blood, and through him come to his people: and these are "sure", firm, and steadfast, through the faithfulness and holiness of God, who has given them to Christ; through being in a covenant ordered in all things and sure; and also being in the hands of Christ, in whom the promises are yea and amen, and the blessings sure to all the seed; see ( Acts 13:34 ) , (See Gill on Acts 13:34).