Bereschit 18:1 Kommentar: Rashi, Be'er Mayim Chaim, Chizkuni & Da'at Zekenim

וירא אליו AND THE LORD APPEARED UNTO HIM to visit the sick man. R. Hama the son of Hanina said: it was the third day after his circumcision and the Holy One, blessed be He, came and enquired after the state of his health (Bava Metzia 86b)

And what appears [correct] to me about this is that it is well known that the secret of the commandment of circumcision is very, very deep - 'who can find it?' And it is greater than all of the positive commandments in the Torah, since there is no commandment from all of the 248 positive commandments for which one is liable excision besides [eating the] Pesach sacrifice and circumcision; and thirteen covenants were sealed upon it; and the essence of creation rests upon it - as per the statement of the Sages, may their memory be blessed (Nedarim 31b), "Rabbi said, etc. Great is circumcision, for were it not for circumcision, the Holy One, blessed be He, would not have created His world - as it is stated (Jeremiah 33:26), 'If it were not for my covenant day and night, I would not have made the laws of heaven and earth.'" For the whole matter of the creation of the worlds was to impact on the creatures with His goodness, to give over from the radiance of His blessing to the world. Yet the whole time the circumcision is covered with the foreskin, the kindnesses cannot descend into the Foundation (Yesod), in order that the external forces not draw sustenance from them, such that no enlightenment comes out from it. So all of the worlds are impacted by harsh judgements (as it is found in the words of the Ari about the intention of circumcision). Hence the world cannot endure with the negation of circumcision. And that is why Scripture stated (Malachi 2:5), "My covenant was with him for life and peace." As every aspect of life - which is the essence of the endurance of creation - is all through the aspect of circumcision. And therefore the numerical count (gemartria) of brit is nine times life (chaim) - since it is in the aspect of the Foundation (associated with circumcision) which is the ninth trait going downwards and the aspect of life descends from every trait to the aspect of the Foundation, and it is the [trait] that gives the bounty of life to those that come to the world. And it is well known from the words of the Ari that the name of the Foundation is peace, because it creates peace among all the traits and every aspect of the kindnesses and the restrictions descend into it. So the restrictions are grouped into the kindnesses there and are sweetened there. And that is why it stated, "My covenant was with him for life and peace" - it is to say that the aspects of life and peace are with the aspect of the covenant, since the whole aspects of life and peace receives their bounty from it, as stated. And that is why thirteen covenants were sealed upon it, to hint to the one aspect within which all the traits unite and which unifies them into one. For it is 'a ladder planted towards the ground and its head reaches to the heavens.' As the bounty that descends upon it descends from a high and very awesome place, the hidden Mind, the Source of mercy and kindnesses, the aspect of the thirteen attributes of mercy. And that is why thirteen covenants were sealed upon it.

וירא אליו, “He appeared to him;” Rabbi Chama son of Rabbi Chanina, claims that this appearance occurred on the third day after Avraham had circumcised himself. (Talmud Babba Metzia 86, and quoted by Rashi.) G-d “visited” him as one visits a sick person. The interpretation by that Rabbi is plausible as we do not find anywhere else that the word: וירא is used without the purpose or message of that appearance being spelled out by the Torah. Other commentators believe that G-d’s appearance to Avraham was necessary in connection with revealing to him what He intended to do to the inhabitants of Sodom and the cities associated with it. The angels’ appearance to Avraham interrupted what G-d had planned to tell him at that point, seeing that one of them at least was charged with saving Lot. A third interpretation: The substance of the word וירא was the visit paid to Avraham by the three angels. It is not unusual for angels to be referred to as “G-d, Divine beings;”the author cites some examples of this being: Exodus 23,21, where G-d explains to Moses that His name his integral to the angel He plans to send ahead of the marching Israelites, and that this is a reason the people must be especially cautious not to offend him. The angel has the authority to react without first obtaining specific permission from G-d to do so. At the burning bush we find another such occasion where G-d and the angels are referred to interchangeably; we also find it at the binding of Yitzchok, when “G-d” is portrayed as commanding Avraham to offer his beloved son as an offering, whereas an “angel” orders him not to harm his son.