Parshas Vayera:
The passuk says Avraham was sitting at the entrance at his tent and behold he saw three anashim and ran from the entrance of his tent.The question is why did the pasuk find it necessary to tell us that he ran from the entrance of his tent when we knew this from the beginning of the passuk?
There is an idea that one who leaves a bais kenesses should not run out because it looks like one is trying to run away from mitzvos. The gemara(berachos 6b) says one should run to mitzvos as well. After learning this gemara the question that comes up is if one finished a mitzvah and are going straight to another mitzvah what does one do? If the mitzvah your going to is greater than the mitzvah you just did then you run right away, if the mitzvah you just did is greater than the one your going to you walk, and if they are equal, one half you walk, and the other half you run.
There is a gmeara in shabbas(127a) that says based on the actions of Avraham we see that hosting guests is greater than meeting the Shechina. Since Rav holds that hosting guests is greater, that is why the passuk mentions that he ran straight away from his tent to show that the mitzvah he is going to do is greater than his previous mitzvah and that is in conformance with the gemara.(Kehillas Yitzchak)