Genesis 26:2

“And the Lord appeared unto him, etc.] In a vision or dream, when he was at Gerar: and said, go not down into Egypt; as his father had done in the like case, and where Isaac thought to have gone, and the rather, as that was a fruitful country; and so the Targum of Jonathan, “and it was in the heart of Isaac to go down into Egypt, and the Lord appeared unto him, etc.” and charged him not to go thither; partly to try his faith in him, and dependence on his providence for support in this time of famine, and partly lest he should think of continuing there, and be unmindful of the promise of the land of Canaan to Abraham’s seed: dwell in the land which I shall tell thee of; even the land of…”

“26:2-5 The Lord assured Isaac that the covenant promises (cp. 12:2-3; 15:5-8; 17:3-8; 22:15-18; 28:13-14) would pass to him because Abraham faithfully listened to God and obeyed all his requirements, commands, decrees, and instructions. These terms were later used in Deuteronomy to describe God’s full legal covenant with Israel. An Israelite reader would immediately think of the complete Torah when hearing these words and be prompted to obey God’s law as Abraham did, though Abraham had only a few commands from the Lord. Through these words, the text emphasizes that Abraham would have obeyed the later commands if he had had them, because he was an obedient servant of the Lord.”