Charles Ellicott Commentary Genesis 13:18

"And Abram moved his tent, and came and dwelt by the oaks of Mamre, which are in Hebron, and built there an altar unto Jehovah." — Genesis 13:18 (ASV)

The plain of Mamre. — (Hebrew, oaks of Mamre. See Genesis 12:6). Mamre was an Amorite, then living, and as he was confederate with Abram, it was apparently with the consent of the Amorites, and by virtue of the treaty entered into with them, that Abram made this oak-grove one of his permanent stations.

Hebron. — That is, alliance. Hebron was perhaps so called from the confederacy formed between Abram and the Amorites, and was apparently the name not only of a city, but of a district, as the oaks of Mamre are described as being “in Hebron.” For its other name, Kirjath-arba, see the note on Genesis 23:2.