Genesis 13:18

Moving therefore Abram his tent, he came and dwelt by the valley of Mamre, which is in Hebron. Hebron is a city situated about twenty-two miles south of Jerusalem, which in the times of Moses was called Arbe or Kiriath-Arba, that is, the city of the Four, because there three patriarchs—Abraham, Isaac, and Jacob—are buried, and Adam the first man, as it is written in the book of Joshua. Later, Hebron received its name from one of the sons of Caleb, as the Words of the days recount. If anyone is moved by how it is now called by this name even before the times of the sons, let him understand that it could have been added in this place by Ezra the priest when he was renewing the sacred Scripture, which had been burned by the Chaldeans, as many such things added by him are found by those skilled in the sacred writings.

Wonderful the extent of the promise; remarkable the depth of generosity of the Lord of us all; extraordinary the degree of the reward conferred by him in his mercy and love on this blessed man and on the descendants destined to be born to him! Hearing this, and amazed at God's unspeakable goodness, the patriarch "struck camp and moved on until settling at the oak of Mamre, which is at Hebron." After accepting the promise … and following Lot's parting, he changed his campsite to the vicinity of the oak of Mamre. Notice his sensible attitude, his high sense of responsibility in effecting the transfer with ease and making no difficulty of changing from place to place. You will not find him shackled and hidebound by any custom, something that frequently affects a great number of people, even those considered wise and those generally free of concerns. If the occasion should require them to change and move in a different direction, even in many cases for a spiritual matter, you would find many of them troubled, beside themselves, regretting the change on account of their being prisoners of habit. The just man, on the other hand, wasn't like that. He showed good sense from the very outset. Like a stranger or a pilgrim he moved from here to there and from there to the next place. And in all cases his concern was to give evidence of his God-fearing attitude in his actions.

And he built an altar to the Lord. And this is the third altar that Abraham built: for the first he built near the place of Shechem, the second between Bethel and Ai. In all of these, it should be noted that nowhere is a sacrifice offered by him, but only the invocation of the name of the Lord is recorded in Scripture; nor in the following Scriptures is it found that he offered any victim or sacrifice to God, except for one ram, which he offered as a burnt offering to the Lord in place of his son, in which the passion of the Mediator between God and men is most clearly figured. Nor is it read that Isaac, his son, offered any victim to God, but only built an altar to the Lord. Similarly, Jacob, though he made an altar at the Lord's command, is not found to have slain any victims, except when, leaving the land of promise, he was about to enter Egypt because of Joseph. Then indeed, arriving in Beersheba, having slain victims there, he is reported to have received a divine oracle; but there both the species and the number of the victims are omitted: nor is any sacrifice offered to God by the fathers found from then until the time of the Passover which was sacrificed in Egypt with the blood of the lamb. Why is it, then, that from the time the promise was made to Abraham until the time the law was given, no victims were offered, except for only one, which the father sacrificed in place of his son in the figure of God the Father, who did not spare his own Son but delivered him up for us all, and that afterward, in the law, such an abundance of victims did not cease to be offered daily, except because it was clearly foreshadowed that the grace and truth promised to Abraham and his seed were to be given to the world not through the offerings of victims, but through the passion of Christ? By whose faith and sacraments of the passion not only we but also those righteous ones who preceded the times of his passion were saved. And this figure is supported by the fact that Melchizedek, the priest of God Most High, who was in the times of the patriarchs, is read to have offered not the blood of victims but bread and wine to the Lord, and to have presented not the form of the legal priesthood, but of the evangelical: who also blessed Abraham himself, to whom and in whom the blessing of all nations was promised, so that it was evident through all things that the promise…