Arboc. Corrupte in nostris codicibus Arboc scribitur, cum in Hebraeis legatur Arbe, id est quattuor, eo quod ibi tres patriarchae, Abraam, Isaac et Iacob, sepulti sunt, et "Adam Magnus", ut in Iesu libro scriptum est: licet eum quidam conditum in loco Calvariae suspicientur. Haec est autem eadem Chebron, olim metropolis Filistinorum et habita-culum gigantum, regnumque postea David, in tribu Iudae civitas sacerdotalis et fugitivorum. Distat ad meridianam plagam ab Aelia milibus circiter viginti duobus.
(Jerome 7:11-18)

Et quercus Abraam, quae et Mambre, usque ad Costantii regis imperium monstrabatur, et mausoleum eius in praesentiarum cernitur, cumque a nostris ibidem ecclesia iam extructa sit, a cunctis in circuitu gentibus terebinthi locus superstitiose colitur, eo quod sub ea Abraam angelos quondam hospitio susceperit. Haec ergo primum Arbe, postea a Chebron, uno filiorum Chaleb sortita vocabulum est. Lege Verba dierum.
(Jerome 7:18-24)

Eusebius, Onomasticon 6:8-12 (ca. 295 A.D.); Jerome 7:18-24 (ca. 390 A.D.)
Arbo (Gen 23:2). In our codices it is written in a corrupted form, 'Arboc', while the Hebrew text reads 'Arba', that is, 'four', because the three patriarchs, Abraham, Isaac and Jacob are buried there, as well as 'the great Adam', as is written in the Book of Joshua (Jos 14:15), although some suppose that he is buried on the Calvary. 'That is Hebron', today a large village, in ancient times one of the main cities of the Philistines [Eusebius: 'the aliens', i.e. the Cannanites in general] and a dwelling place of giants, and later royal seat of David. It fell into the lot of the tribe of Judah, and was a priestly city and one of the cities of refuge. It is south of Jerusalem at a distance of about 20 [22] miles.

Eusebius, Onomasticon 6:12-16 (ca. 295 A.D.);Jerome 7:18-24 (ca. 390 A.D.)
The oak of Abraham, also called Mambre, could be seen standing until the reign of Constantius, and the tomb of the same is visible to this day and while a church has been erected there by our people, the place of the oak is [greatly] venerated by all the pagan population around, because under it Abraham gave hospitality to the angels. At first the place was called Arbe, and later it was named Hebron after Hebron, one of the sons of Caleb, as we read in the Chronicles. (1Chron 2:42).

BIBLICAL BACKGROUND

Gen 13:18 Abram settles in Mamre
Abram moved his tent, and came and settled by the oaks of Mamre, which are at Hebron; and there he built an altar to the Lord.

Gen 18:1-15 The apparition at Mamre
The Lord appeared to Abraham by the oaks of Mamre, as he sat at the entrance of his tent in the heat of the day. 2 He looked up and saw three men standing near him. When he saw them, he ran from the tent entrance to meet them, and bowed down to the ground. 3 He said, "My lord, if I find favor with you, do not pass by your servant. 4 Let a little water be brought, and wash your feet, and rest yourselves under the tree. 5 Let me bring a little bread, that you may refresh yourselves, and after that you may pass on - since you have come to your servant." So they said, "Do as you have said." 6 And Abraham hastened into the tent to Sarah, and said, "Make ready quickly three measures of choice flour, knead it, and make cakes." 7 Abraham ran to the herd, and took a calf, tender and good, and gave it to the servant, who hastened to prepare it. 8 Then he took curds and milk and the calf that he had prepared, and set it before them; and he stood by them under the tree while they ate.
9 They said to him, "Where is your wife Sarah?" And he said, "There, in the tent." 10 Then one said, "I will surely return to you in due season, and your wife Sarah shall have a son." And Sarah was listening at the tent entrance behind him. 11 Now Abraham and Sarah were old, advanced in age; it had ceased to be with Sarah after the manner of women. 12 So Sarah laughed to herself, saying, "After I have grown old, and my husband is old, shall I have pleasure?" 13 The Lord said to Abraham, "Why did Sarah laugh, and say, 'Shall I indeed bear a child, now that I am old?' 14 Is anything too wonderful for the Lord? At the set time I will return to you, in due season, and Sarah shall have a son." 15 But Sarah denied, saying, "I did not laugh"; for she was afraid. He said, "Oh yes, you did laugh."

Gen 23:1-20 The tombs of the patriarchs
Sarah lived one hundred twenty-seven years; this was the length of Sarah's life. 2 And Sarah died at Kiriath-arba (that is, Hebron) in the land of Canaan; and Abraham went in to mourn for Sarah and to weep for her. 3 Abraham rose up from beside his dead, and said to the Hittites, 4 "I am a stranger and an alien residing among you; give me property among you for a burying place, so that I may bury my dead out of my sight." 5 The Hittites answered Abraham, 6 "Hear us, my lord; you are a mighty prince among us. Bury your dead in the choicest of our burial places; none of us will withhold from you any burial ground for burying your dead." 7 Abraham rose and bowed to the Hittites, the people of the land. 8 He said to them, "If you are willing that I should bury my dead out of my sight, hear me, and entreat for me Ephron son of Zohar, 9 so that he may give me the cave of Machpelah, which he owns; it is at the end of his field. For the full price let him give it to me in your presence as a possession for a burying place." 10 Now Ephron was sitting among the Hittites; and Ephron the Hittite answered Abraham in the hearing of the Hittites, of all who went in at the gate of his city, 11 "No, my lord, hear me; I give you the field, and I give you the cave that is in it; in the presence of my people I give it to you; bury your dead." 12 Then Abraham bowed down before the people of the land. 13 He said to Ephron in the hearing of the people of the land, "If you only will listen to me! I will give the price of the field; accept it from me, so that I may bury my dead there." 14 Ephron answered Abraham, 15 "My lord, listen to me; a piece of land worth four hundred shekels of silver - what is that between you and me? Bury your dead." 16 Abraham agreed with Ephron; and Abraham weighed out for Ephron the silver that he had named in the hearing of the Hittites, four hundred shekels of silver, according to the weights current among the merchants.
17 So the field of Ephron in Machpelah, which was to the east of Mamre, the field with the cave that was in it and all the trees that were in the field, throughout its whole area, passed 18 to Abraham as a possession in the presence of the Hittites, in the presence of all who went in at the gate of his city. 19 After this, Abraham buried Sarah his wife in the cave of the field of Machpelah facing Mamre (that is, Hebron) in the land of Canaan. 20 The field and the cave that is in it passed from the Hittites into Abraham's possession as a burying place.

Josh 14:13-15 Hebron assigned to Caleb
Then Joshua blessed him, and gave Hebron to Caleb son of Jephunneh for an inheritance. 14 So Hebron became the inheritance of Caleb son of Jephunneh the Kenizzite to this day, because he wholeheartedly followed the Lord, the God of Israel. 15 Now the name of Hebron formerly was Kiriath-arba; this Arba was the greatest man among the Anakim. And the land had rest from war.

2Sam 5:1-5 David is anointed king of Israel
Then all the tribes of Israel came to David at Hebron, and said, "Look, we are your bone and flesh. 2 For some time, while Saul was king over us, it was you who led out Israel and brought it in. The Lord said to you: It is you who shall be shepherd of my people Israel, you who shall be ruler over Israel." 3 So all the elders of Israel came to the king at Hebron; and King David made a covenant with them at Hebron before the Lord, and they anointed David king over Israel. 4 David was thirty years old when he began to reign, and he reigned forty years. 5 At Hebron he reigned over Judah seven years and six months; and at Jerusalem he reigned over all Israel and Judah thirty-three years.

MORE ANCIENT SOURCES

Josephus, War 4,533 (1st cent. A.D.)
There is also there shown, at the distance of six furlongs from the city, a very large turpentine tree;2 and the report goes, that this tree has continued ever since the creation of the world.

Eusebius, Onomasticon 76:1-3 (ca. 295 A.D.)
The tree of Mambre, that is the terebinth, is shown at present near Hebron. There Abraham put his tent. It is venerated also by the heathens.

Jerome's latin translation of Eusebius, Onomasticon 77:1-5 (ca. 390 A.D.)
The tree, that is the oak, of Mambre near Hebron, is a very old terebinth which was shown till the time of Emperor Constantius, when I was a child. Its size used to gave an hint about its age. Under that tree Abraham dwelt. It is worshipped by the heathens in an amazing manner, as it was consecrated by old with a remarkable fame.

Itinerarium Burdigalense 599 (333 A.D.)
Fourteen miles away is Bethsur, at which is the spring where Philip baptized the eunuch. It is nine miles to Terebinthus, where Abraham lives and dug a well beneath the terebinth tree, and spoke and ate with the angels; An exceptionally beautiful basilica has been built there by command of Constantine.Two miles on from there is Hebron, where there is a remarkably beautiful tomb, square and made of stone, in which are laid Abraham, Isaac, and Jacob, and Sarah, Rebecca, and Leah.

Sozomenus, Historia Ecclesiastica II,4 (5th cent. A.D.)
I deem necessary to declare now what was resolved about the oak of Mambre by Emperor Constantine. The place is presently called the Terebinth, and is situated at the distance of fifteen stadia from Hebron, which is to the south... Every year, at summer time, the inhabitants of that place and the Palestinians, the Phoenicians and the Arabs, coming from far away, make a fair there. Many come there for the sake of business, some to sell and some to buy. The feast is celebrated by a very big congregation of Jews, since they boast of Abraham as their forefather, of heathens since angels came there, of Christians since he who should be born from the Virgin for the salvation of humankind appeared there to that pious man. Everyone venerates this place according to his religion: some praying God the ruler of all, some calling upon the angels and offering libations of wine, burning incense or sacrificing an ox, a pig, a sheep or a cock... Constantine's mother in law (Euthropia), having come there to fulfill a vow, gave notice of all this to the Emperor. So he wrote to the bishops of Palestine reproaching them for having forgot their mission and permitted such a most holy place to be defiled by those libations and sacrifices.

Anonymus Placentinus, Itinerarium 30 (ca. 570 A.D.)
From Bethlehem it is twenty-four miles to the Oak of Mamre, the resting-place of Abraham, Isaac, Jacob, and Sarah and also of Joseph's bones. The basilica has four porticoes and no roof over the central court. Down the middle runs a screen. Christians come in on one side and Jews on the other, and they use much incense. On the day following Christ's Birthday the people of this area celebrate the Deposition of Jacob and David with much devotion, and Jews from all over the country congregate for this, too great a crowd to count. They offer much incense and lights, and give presents to those who minister there.