גֵּר־וְתוֹשָׁ֥ב אָנֹכִ֖י עִמָּכֶ֑ם תְּנ֨וּ לִ֤י אֲחֻזַּת־קֶ֙בֶר֙ עִמָּכֶ֔ם וְאֶקְבְּרָ֥ה מֵתִ֖י מִלְּפָנָֽי׃
'Я незнакомец и сожитель с вами: дайте мне владение местом погребения с вами, чтобы я мог похоронить своих мертвецов из виду.'
Rashi
גר ותושב אנכי עמכם I AM A STRANGER AND A SETTLER WITH YOU — A stranger having come from another land, but I have settled down amongst you. A Midrashic explanation is: if you agree to sell me the land then I will regard myself as a stranger and will pay for it, but if not, I shall claim it as a settler and will take it as my legal right, because the Holy One, blessed be He, said to me, (12:7) “Unto thy seed I give this land" (Genesis Rabbah 58:6).
Chizkuni
גר ותושב אנכי עמכם, “I am a stranger as well as a resident amongst you.” A stranger because I came from a foreign land – and a resident because I intend to settle amongst you. Rashi suggests that Avraham also implied that if he were to be denied his request he would insist on his legal rights in the matter (by simply becoming a permanent resident). If you were to point out that according to what Rashi had explained on Genesis 13,7 where the Canaanites are described as the then residents of that land, that had been before he had become a father of children. (Such people cannot claim permanent resident status.) After all, G-d had not promised Avraham that he would inherit this land. He had only promised it to Avraham’s descendants. Now that Yitzchok had been born, he was entitled to inherit part of the Land.
Ramban
I AM A STRANGER AND SOJOURNER WITH YOU. It was customary for them to have separate burial grounds for each family and one burial ground for the internment of all strangers. Now Abraham said to the children of Heth: “I am a stranger from another land and have not inherited a burial ground in this land from my ancestors. Now I am a sojourner with you since I have desired to dwell in this land. Therefore give me a burying-place for an everlasting possession just as one of you.” However, since Abraham used the word “t’nu (give), [which has the same root as matanah,” (gift)], they suspected that he desired it from them as a gift. They therefore answered him: “You are not regarded by us as a stranger or sojourner. Rather, you are a king. G-d has made you king over us, and we and our land are subservient to you. Take any burial ground you desire, and bury your dead there. It shall be unto you a possession of a burial-place forever since no one of us shall withhold it from you.”