Sforno on Genesis 28:4/ספורנו על בראשית כ״ח:ד׳

1ויתן לך את ברכת אברהם, when He had said (12,2) “become a source of blessing!” This involves his teaching people about monotheism, the acceptance of which would result in tangible blessings for those people from G’d. This in turn would make the people regard Avraham as responsible for the blessings they receive. לך ולזרעך אתך לרשתך, if the children would also be following in the footsteps of their parents acting as spiritual instructors to the people around them, their claim to this land would be reinforced. This would become an irreversible sanctification of the name of the Lord. Isaiah 49,3 described this as G’d saying: ישראל אשר בך אתפאר, “Israel in whom I am glorified.” This is also an example of what David had in mind when he said in Psalms 104,31 “G’d delights in His handiwork.”

2ארץ מגוריך, the land of Canaan in which you dwell at the present time.