Chasidut for Bava Metzia 172:3

While on the subject of the meal Avraham prepared for these ‎heavenly guests, we need to understand why he served them ‎meat instead of fish. The motivation may have been to afford his ‎guests to perform many commandments in short order; in the ‎terrestrial regions, nowadays, before being able to consume a ‎meat meal many more commandments must be fulfilled than ‎before preparing a fish meal. This is in contrast with the world to ‎come, where, according to our tradition, G’d will present the ‎righteous with a meal consisting of the Leviathan. There are ‎many more commandments associated with the preparation of a ‎meaty meal than with the preparation of a “fish meal,” i.e. ‎Leviathan. (Baba Metzia 86) According to the Talmud, Avraham ‎slaughtered three calves in order to be able to offer each of his ‎guests a tongue and mustard (as seasoning), considered the ‎choicest meat of the animal.‎
The Talmud Eyruvin 53 relates that when Rabbi Yossi ‎bar Avion wished to say something that only people familiar with ‎him would understand, he would say: ”‎עשו לי שור במשפט בטור ‏מסכן‎;“ he deliberately used some Hebrew words, ‎שור‎, ‎במשפט‎, ‎which have a different meaning in Aramaic. Similarly, the word ‎חרדל‎ used by our sages for the seasoning Avraham provided for ‎his guests is really a translation of the words ‎הר דל‎, “a low hill.” In ‎short, the Rabbi making excuses for the errors committed by the ‎Jewish people, referred to the evil urge as an almost ‎insurmountable obstacle, a tall mountain, whereas the urge to do ‎good given to every human being, appeared like a low hill, so that ‎it is not surprising that many Jews many times found it difficult ‎to climb over the tall mountain in order to avoid sinning. When ‎the sages spoke of the “seasoning” Avraham served his guests, ‎this is merely a euphemism for saying that he tried to provide his ‎guests with merits by the type of food served that would make it ‎relatively easy to overcome the temptations offered by the evil ‎urge. When the angels would reflect on this, they in turn, in the ‎future, would tone down their accusations against sinful Jews, ‎having realized through their visit on earth how difficult it is to ‎fight these temptations.