John Gill Bible Commentary

Then i will also remember my covenant with Jacob,.... Would fulfil and make good all that he had promised in covenant with Jacob, and his posterity: the account begins with him, and rises upwards to Abraham, whereas it usually begins with Abraham, and descends to Jacob; no sufficient reason is given for this alteration, though several are attempted by the Jewish writers (e): and also my covenant with Isaac, and also my covenant with Abraham will I remember; which chiefly respects the multiplication of their seed, the continuance of them, and the Messiah springing from them; which is the mercy promised to these fathers, and the principal part of the covenant made with them, and which was remembered and performed when God visited and redeemed his people by him, Luk 1:68, and I will remember the land; the land of Judea, and return the Jews to it, and make it fruitful, after he had given it rest from tillage for many years, which was fulfilled at their return from the captivity of Babylon. (e) Saadiah Gaon apud Aben Ezram in loc. Pesikta & alii.