GEN912 [T]he holy Torah itself relates in Pashas VaYeira Genesis 18:1-8 how Avraham Avinu brought guests into his home with great love and warmth, even though he was convinced that they were “Arabs who bow down to the dust of their feet.” [Rashi’s commentary on Genesis 18:4, based on Bava Metzia 86b].   In verse three, Avraham implores, “My masters! If I have found favor in your eyes, please do not pass away from your servant.”  The Ramban comments:  In my opinion, the correct reading of this verse is that Avraham first addressed them all as “my masters.” He then turned to each [and addressed them] individually. [In this passage, the Ramban seeks to explain a peculiarity that he points out earlier, namely, that Avraham first addresses the passerby in the plural, then in the singular, and then again in the plural]. To the first, he said, “If I have found favor in your eyes, please do not pass away from your servant.” He repeated this statement to the second visitor and the third, as well.   That is, he entreated each one individually [in this manner.] He then said to all of them, “Let a little water be fetched, and you can all wash your fee.” He addressed them in this courteous and respectful manner out of his great desire to be benevolent to his guests.   It should be noted that Avraham perceived that these were wayfarers, and that they had no desire to loge with him. This is why he only requested that they take a little water to wash their feet on account of the heat – to put “cold water on a weary soul” [Based on the language of Proverbs 25:25] – and that they recline beneath the tree in the afternoon breeze, without asking them to come indoors to the tent.   It is not for nothing that the Torah expounds at such length in the recounting of the story, providing more meticulous details than it does with respect to the laws of issur ve’heter.   [The laws of keeping kosher, which are amongst the most detailed and complex in the Torah].   Though this, we learn that compassion is the very essence of a Jew, and that if one is not merciful towards his fellow men, he cannot be of the descendants of Avraham.  EYES 107-8