Vayeira Rashi (18;2) relates that Hashem sent Avraham 3 angels-one of which was sent to tell Sarah that she was going to give birth, another to tell Avraham that Hashem was going to destroy Sodom, and the third was to heal Avraham. However, none of these angels were needed! Firstly, Hashem had already promised that Sarah was going to have a child 3 days earlier (17;16)! Therefore, there was no n…