ARBA is named 'the father of the Anak' in Jos 14:15 (so read also Jos 21:11, cf. Jos 15:13). This means simply that he was the founder of the city which bore his name; that is Kiriath-arba, later Hebron (wh. see), where was a chief seat of the Anakim.
J. F. McCurdy.
Hebron's name used to be Kiriath-arba; Arba was the greatest man among the Anakim. After this, the land had rest from war.
He gave Caleb son of Jephunneh [the following] portion among the descendants of Judah based on the Lord's instruction to Joshua: Kiriath-arba (that is, Hebron; Arba was the father of Anak).
They gave them Kiriath-arba (that is, Hebron) with its surrounding pasturelands in the hill country of Judah. Arba was the father of Anak.
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