וְהִנֵּ֨ה יְהוָ֜ה נִצָּ֣ב עָלָיו֮ וַיֹּאמַר֒ אֲנִ֣י יְהוָ֗ה אֱלֹהֵי֙ אַבְרָהָ֣ם אָבִ֔יךָ וֵאלֹהֵ֖י יִצְחָ֑ק הָאָ֗רֶץ אֲשֶׁ֤ר אַתָּה֙ שֹׁכֵ֣ב עָלֶ֔יהָ לְךָ֥ אֶתְּנֶ֖נָּה וּלְזַרְעֶֽךָ׃
And, behold, the LORD stood beside him, and said: ‘I am the LORD, the God of Abraham thy father, and the God of Isaac. The land whereon thou liest, to thee will I give it, and to thy seed.
Rashi on Genesis
נצב עליו STOOD ABOVE HIM to guard him (Genesis Rabbah 69:3).
Rashbam on Genesis
הארץ אשר אתה שוכב עליה לך אתננה ולזרעך, if you were to say that this promise entails so very little, I am adding that your descendants will spread out in all directions of the globe.
Sforno on Genesis
הארץ אשר אתה שוכב עליה, a reference to the region currently known as “the land of Canaan,”