Musar su Genesi 19:29

We have learned that at a time when G–d loves man He sends him a gift. What is this gift? A poor person. G–d extends this opportunity to perform a deed of loving kindness with the poor. When such a good deed has been performed by such a person, G–d provides more of a thread of חסד which originates in the 'right' side of the emanations, and He spreads this thread over the head of the person who looked after the poor. He makes a mark on that person's head so that, when judgment engulfs his environment, the executing angel should beware not to touch the individual so marked by G–d. When G–d was about to destroy Sodom, He first provided Abraham with the merit of entertaining the three angels so that through the meeting he would have a chance to save Lot his nephew by using their good services. This is the meaning of 'G–d remembered Abraham and sent Lot away from the destruction' (19,29). The Torah does not say that 'G–d remembered Lot.' He was saved by the merit of Abraham. What was it that G–d remembered? It refers to Abraham's treatment of the angels. G–d remembers the charitable deeds of a person at the time when destructive forces are allowed free reign. All these good deeds performed are recorded in Heaven. This is the meaning of וצדקה תציל ממות, 'and charity saves one from death' (Proverbs 10,2). This is why G–d arranged for Abraham to have the opportunity to perform an act of charity which could serve as an excuse to save Lot." Thus far the Zohar on the subject (Sullam edition Vayera 52).