בראשית כג:ט פירוש: רש״י, רמב״ן, רשב״ם וספורנו

המכפלה MACHPELAH (the root, כפל, means double) — it had a lower and an upper cavern. Another explanation of why it was so called is, because it has the characteristic of being doubled on account of the couples who are buried there (see Rashi in verse 2) (Eruvin 53a).

THAT HE MAY GIVE ME. The intent of this is “that he may give it to me in such a way that I will consider it as a gift (even) if I will buy it from him for its full value.” It is for this reason that Abraham did not mention the word “selling.” A similar usage is found in the verse, Thou shalt sell me food for money, that I may eat; and give me water for money, that I may drink,³⁰Deuteronomy 2:28. meaning “for the water which is usually given as a gift I will give money.” It may be that such is the ordinary usage of the language to mention “giving” when describing sales transactions.

מערת המכפלה, any depression in the surface of the earth is called מכפלה, as the ככר הירדן, refers to the entire Jordan valley (13,10). This is substantiated by the Torah describing Efron’s field as being located in מכפלה in verse 18 of our chapter.