“וירא אליו ד' באלוני ממרא, והוא יושב פתח האוהל כחם היום” – “Hashem appeared to him (Avrohom Avinu) in the plains of Mamre, while he was sitting at the entrance of the tent in the heat of the day.” We know that Hakodosh Boruch Hu appeared to Avrohom Avinu, but why doesn’t the Torah say it explicitly, “וירא ד' אל אברהם”? The Midrash Tanchuma says that Hakodosh Boruch Hu told the Malachim, “Come, let’s go visit the sick person.” The Malachim responded to Hakodosh Boruch Hu: Why do You want to go to a place of filth and dirt, etc...? Hakodosh Boruch Hu just told the Malachim that they were going to go visit a sick person, but didn’t say that it was Avrohom that they were going to visit. Hakodosh Boruch Hu did not reveal Avrohom’s name for He knew that the Malachim would have even more complaints, as Avrohom Avinu had already received a letter from the Name of Hakodosh Boruch Hu, the letter ה' which was added to Avrohom Avinu’s name. The Torah does not say Avrohom’s name in these Pesukim to teach us that He did not reveal to the Malachim that they were going to visit Avrohom, so they would not be jealous and come to cast aspersions on Avrohom.
