Although our forefather Avraham fulfilled the entire Torah, the Torah did not elaborate on all the commandments he kept, but only summarized them in general: Because Abraham obeyed My voice, and observed My safeguards, My commandments, My decrees, and My Torahs (Bereishis 26:5). Yet with regard to the mitzvah of hosting guests the Torah recounts his deed in great detail. The reason for this is that we are to learn from it the proper manner of hosting guests. First the Torah recounts that although Avraham was still not well from his circumcision, he nevertheless sat at the opening of his tent in order to see whether there were any wayfarers who might need hospitality. And although our level is not that high, still, we can at least learn from that that one must actively look for guests and to greet them with extra warmth, just as one would do if a very wealthy individual came to his house and the host would have an opportunity to earn a great profit.
