לְאַבְרָהָ֥ם לְמִקְנָ֖ה לְעֵינֵ֣י בְנֵי־חֵ֑ת בְּכֹ֖ל בָּאֵ֥י שַֽׁעַר־עִירֽוֹ׃
à Abraham, comme acquisition, en présence des enfants de Heth, de tous ceux qui étaient venus à la porte de la ville.
Ramban
IN THE PRESENCE OF THE SONS OF MY PEOPLE. The intent thereof is to state: “Behold, all the people are present, and they are knowledgeable witnesses to the sale. Therefore do not fear denial or retraction, and so bury thy dead from now on, for it is yours and I cannot retract.” But Abraham did not do so for even after he paid its full value in silver he first took symbolic legal possession of the field and the cave. He established them as his possession in the presence of the people of the city, and all those who came in at the gate of the city,33Verse 18 here. the merchants and the residents who happened to be there, and after that he buried her.
Ibn Ezra
He who is now thy ally, and will then become thy enemy, will fall.29This explanation seems to be based on the meaning of the two prepositions אתך and את ;עליך with indicates alliance, friendship; על against, enmity and war. I take גור יגור in its usual meaning and explain the verse thus: Can there dwell any stranger with thee in my land, except it be with my will; he who desires to dwell with thee in my land, עליך יפול must surrender to thee.30A. V., Shall fall for thy sake. The verb נפל has here the same meaning as in אל הכשדים אתה נופל thou fallest away to the Chaldӕans (Jer. 37:13); and in על פני כל אחיו נפל he surrendered to all his brethren (Gen. 25:18); namely: to submit to the authority of.31In his commentary on Gen. 23:18, I. E. gives three meanings of the verb נפל in the two passages quoted here: 1. His lot or portion fell. 2. He went away. 3. He died. The meaning adopted here to surrender, is not even mentioned there.
Rashi
ויקם שדה עפרון AND THE FIELD OF EPHRON WAS MADE SURE (literally, it rose) — It received a rise in importance because it passed from the possession of a commoner (הדיוט an ordinary person) into the possession of a king (Genesis Rabbah 58:8). But the real meaning of the verse is: The field and the cave that was therein and all the trees … became secured to Abraham as a possession etc. (i. e. verse 17 is an incomplete sentence and must be read together with verse 18, thus: ויקם השדה וגו… לאברהם למקנה —The field etc. became secured to Abraham as a possession).