Sforno on Genesis 17:8/ספורנו על בראשית י״ז:ח׳

1לאחוזת עולם, "I will be your G'd in order that you may carry out My will, and He gave them the land presently belonging to other nations in order that they keep His statutes." (Psalms 105, 44-45) When they do this they will achieve eternal existence individually, not merely as a species.