Thou wilt perform the truth to Jacob,.... That is, the promise made to Jacob, the Lord would faithfully perform and make good to his posterity, natural and spiritual, especially to those who are Israelites indeed;[and] the mercy to Abraham; the gracious promises made to him, which sprung from mere grace and mercy; all respecting his natural and spiritual seed; and especially the promise of the coming of the Messiah, that seed of his in which all nations of the earth were to be blessed; and which is the eminent instance of the mercy and grace of God to Jews and Gentiles, that walk in the steps of Abraham; see Lu 1:68;which thou hast sworn unto our fathers from the days of old; or the promises both of multiplying the seed of Abraham, and of giving them the land of Canaan, and of the Messiah springing from them, were confirmed by an oath, Ge 22:16.
The Targum is,"thou wilt give the truth of Jacob to his sons, as thou hast sworn to him in Bethel; the goodness of Abraham to his seed after him, as thou hast sworn to him between the pieces; thou wilt remember to us the binding of Isaac, who was bound upon the altar before thee; thou wilt do with us the good things which thou hast sworn to our fathers, from the days of old;''which Kimchi interprets of the three fathers, Abraham, Isaac, and Jacob.