Rashi on Genesis 28:13/רש"י על בראשית כ״ח:י״ג

1נצב עליו STOOD ABOVE HIM to guard him (Genesis Rabbah 69:3).

2ואלהי יצחק AND THE GOD OF ISAAC — Although we do not find in the Scriptures that God associates his Name with that of the righteous whilst they are yet alive by writing, “The God of so-and-so”, — because it is said (Job 15:15) “Behold He putteth no trust even in His holy ones” — here, however, He associated his Name with that of Isaac because his eyes had become dim and he was confined to the house, so that he might be regarded as dead and as though the evil inclination had already passed away from him and he was unlikely to sin any more (Midrash Tanchuma, Toldot 7).

3שכב עליה THE LAND WHEREON THOU LIEST — The Holy One, blessed be He, rolled together the entire Land of Israel under him, thus intimating to him that it would be as easily conquered by his descendants (Chullin 91b) as a piece of land four cubits in length, which is the space covered by a person lying down (see Rashi, Chullin 91b, and the note of the ב"ח thereon).