Chasidut sobre Génesis 18:1

And Hashem appeared to him etc (Genesis 18:1) - we have to explain first the verse "And Avraham was old, entered in days" (Genesis 24:1). Behold, the upper worlds are called "days" and the tzadik in their kedusha reaches up to the upper worlds, and this is "Avraham was old/zaken" as in "this one acquired wisdom"/Zeh Kanah chochmah" (Sifra, Kedoshim 7:12); "entered in days" meaning, until he reached the upper worlds, and so too about King David, peace be upon him, it was said "And David was old, entered in days etc" (I Kings 1:1) and this is "He asked from You life; You granted him many days" (Ps. 21:5). That behold regarding the tzadik, the life they have in this world is not his, rather, it is as a borrowed thing for one hour, and because of this the tzadik goes and strengthens themself always in holiness, since the tzadik always thinks that lest today it will be the day of returning what was borrowed, and this is "he asked from You life", meaning, meaning, the tzadik who thinks that life is only borrowed from You, therefore "You granted him many days", through this the tzadik merits many days, which are the life in the world to come.

‎Genesis 18,1. “Hashem appeared to him (Avraham) in the ‎groves of Mamre.” Since we have been told that G’d had ‎departed from Avraham in 17,23, we would have expected the ‎verse here to mention the subject Avraham by name. Why does ‎the Torah only write ‎לו‎, “to him?”
G’d, i.e. aspects of the ‎אין ‏סוף‎, G’ds Essence, dispensed different amounts of ‎שפע‎, “original ‎light,” eventually converted in the lower domains of the universe ‎into matter of varying degrees of physical densities. Every such ‎שפע‎, represents a distillation, ‎צמצום‎, “shrinkage, of this original ‎light. [If I understood the concept correctly, Ed.] This process is ‎reflected already in the different names we have for G’d, the ‎letters in these names reflecting varying degrees of G’d’s having ‎restricted His manifestations to His creatures in order to make it ‎compatible with what His creature can tolerate.
This principle ‎applies not only to creatures in the lower part of the universe, i.e. ‎our planet, but also to the different categories of “angels,” ‎disembodied servants of the Lord in the celestial spheres, ‎according to the spiritual level attained by the creature, angel, or ‎human being, as the case may be.
When such a human being ‎has been given a “name” by its Creator, this “name” reflects the ‎degree to which this person is able to absorb G’d’s “light,” ‎without being harmed by it. When a human being serves his ‎Creator out of awe, ‎יראה‎, by totally negating the limitations ‎imposed on a soul while it is constricted by the body it inhabits, it ‎may be considered as having “disrobed,” shed the restrictions his ‎body imposed upon the free, upward, heavenward motion of his ‎soul. When we express this concept in terms of the meaning of ‎the letters in our G’d-given names, this means that we have ‎divested ourselves of our “names.”
Avraham, at the time of his ‎life that the Torah speaks about here, had not yet freed himself ‎from the limits imposed upon him (by dint of the letters in his ‎name) prior to his having been circumcised. This state of flux, a ‎temporary situation, in which Avraham found himself at the ‎beginning of this portion, is reflected in the Torah referring to him ‎only by a pronoun, instead of by his full name.‎

And the LORD appeared to him by the oaks of Mamre, as he sat at the door of his tent in the heat of the day. He lifted up his eyes and looked, and behold, three [men were standing in front of him]. When he saw them, he ran to meet them from the tent door and bowed himself to the earth (Gen. 18:1-2). It is written in the Holy Zohar, “Who were these three men? Abraham, Isaac, and Jacob” (Zohar 1:98a). Now, it is known that the Holy Torah must be in every person and in every time, since it is eternal; but the truth is that the Blessed Creator is found in each Jew, and even in the most wicked person and in the worst sinner, God forbid. And the proof is that every wicked person has notions of teshuvah each day, and that is [the meaning of] Blessed God’s appearing to him. And when he goes with this, when he elevates his mind, then he begins to ask, “When will my actions arrive at the actions of my Ancestors?” (cf. Tanna D’Vei Eliyahu Rabbah [Friedmann ed.] ch. 23). For the Ancestors are themselves the chariot; and what is the chariot? It is written in Tikkunei Zohar, “The horse is secondary to the rider, but the rider is not secondary to the horse” (Tikkun 70, 134a) such that the horse could go any place it wants, leading him into the river and to filthy places; instead, it must go to the place where the rider wills it to go. And when a person is a chariot for [God’s] Great Name, he goes only to the place where Blessed God wants [him to go], he does only Blessed God’s will and not the Evil Inclination’s will.