In an article for Chayei Sarah 5774, Rabbi Cherki explains the two different ways Abraham and the people of Heth viewed the purchase of the Machpelah Cave.
Our Patriarch Abraham wanted to have some property among the children of Heth, to be considered as a citizen of the land. He therefore presents the ways that he is similar to them: "I am a stranger and a resident" [Genesis 23:4]. From the point of view of his soul, Abraham feels that he is a stranger in the world, but from the point of view of nature he is an inhabitant. He also adds that the people of Heth have the same trait, by saying "together with you" [ibid]. But they do not accept his argument, which attempts to combine the two forms of human existence into one personality. Rather, they feel that there are two types of human beings, either spiritual or earthly. They insist that Abraham is a "prince of G-d" while they are "people of the earth." They therefore refuse to give him a burial plot, which would give him the status of a citizen of the land, but want to give him permission to use their burial plots, without any rights of possession.
Abraham receives support from the initiative of Ephron Ben Tzohar, who recognizes Abraham's ability to lift up humanity from its lowly position. His very name is testimony that he knows that humanity at its root was white and pure ("tzachor") and later took on the traits of dust ("afar" – similar to Ephron). He anticipates that Abraham will lift up humanity, as is written, "And the field of Ephron rose up" [23:17], when he attaches himself to Adam's burial site.
A cave is not a site for agriculture but rather for burial. The first use of a field is for agriculture, and after the fact it might be used as a burial ground too. Abraham wants to buy only the cave, in order to emphasize that it is meant as a burial site, a possession that in the ancient laws is a sign of permanent citizenship. Ephron explains that the people of Heth will not allow this, and he therefore proposes that Abraham buy the field, which will give him possession of the cave as part of the purchase. However, then the people of Heth would claim that the area was not a formal burial plot but rather an agricultural area which is being used in an unusual way, as a burial plot.
Ephron has a brilliant solution to this dilemma. Land is bought by paying money or by performing an act of taking possession. If the transaction will consist of a transfer of money, the children of Heth will be able to claim that the property is merely agricultural land. But if the purchase will be sealed by an act of possession, the status of the plot will depend on what action Abraham takes. If he plants trees, the area is mainly a field, but if he buries somebody, it is a burial field. "In the eyes of the children of Heth" [24:18], the element of greatest importance was the money, so as far as they were concerned the transfer of money was the end of the process. However, Ephron tells Abraham, "Listen to me" [23:15]. He clarifies that as far as he and Abraham are concerned the money is not important, "between you and me, what importance does it have?" [ibid] – and not the way that the people of Heth feel about the matter. Bury your dead body, and only then will the transfer of ownership take place.
Abraham takes Ephron's advice, "And Abraham listened to Ephron" [23:16]. As a result, the purchase was viewed in two different ways. "And Ephron's field, the field and the cave in it, and all the trees in the field" – emphasizing the agricultural aspect of the transaction – "became a purchase by Abraham, in the eyes of the children of Heth" [23:17-18]. And what happens then? "Afterwards, Abraham buried his wife Sarah in the cave of the field of Machpela in the area of Mamre" [23:19]. Only then, is it written, "And the field and the cave within it were transferred to Abraham as a heritage for burial, bought from the children of Heth." [23:20].
Source: "AS SHABBAT APPROACHES" – a biweekly column in Shabbat B'Shabbato, Chayei Sarah 5774, Volume 1496. (Zomet Institute) See: www.zomet.org.il/eng