In The City

 Avraham prays that if their are righteous people in the city, Sedom should be saved.  Why use the words בתוך העיר, we know we are talking about Sedom?  (See the Ramban.)  A couple of weeks ago we cited the Seforno that a tzaddik can only affect a town if he reprimands and uplifts the people.  The tzaddik can save them only if he has a chance to  connect to them and mend their ways.  That is what Avraham was saying, he wasn't giving their address but rather that the actions of the righteous people must be בתוך העיר, affecting the city, in order for them to be saved (see Rav Hirsch.)

Hav Hirsch at the beginning of the parsha expounds on the idea that immediately after Avraham is singled out by Hashem for a bris, he is sitting in his tent looking to intermingle with others.  The Midrash Lech Lecha (47:10) says אָמַר אַבְרָהָם, עַד שֶׁלֹא מַלְתִּי הָיוּ הָעוֹבְרִים וְהַשָּׁבִים בָּאִים אֶצְלִי, תֹּאמַר מִשֶּׁמַּלְתִּי אֵינָן בָּאִים אֶצְלִי.  Rav Hirsch understands that Avraham was concerned that now that his life's mission of spreading monotheism would be nullified for he stands alone.  Avraham was not just concerned about the עיר, he wanted to affect everyone.  The midrash concludes  אָמַר לוֹ הַקָּדוֹשׁ בָּרוּךְ הוּא עַד שֶׁלֹא מַלְתָּ הָיוּ בְּנֵי אָדָם בָּאִים אֶצְלְךָ, עַכְשָׁיו אֲנִי בִּכְבוֹדִי בָּא וְנִגְלֶה עָלֶיךָ, הֲדָא הוּא דִכְתִיב (בראשית יח, א): וַיֵּרָא אֵלָיו ה' בְּאֵלֹנֵי מַמְרֵא.  According to Rav Hirsch we have to understand that Hashem is not detracting from Avraham's concern.  The response is that that we are now further empowered to carry on the mission of teaching the the ways of Hashem to others because we are further connected to Hashem. 

However ,we could learn the conclusion of the midrash is the opposite of Rav Hirsch.  Once Avraham has been singled out as special, then this relationship is more important than preaching to others.  This may be rooted in the machlokes Rashi and Ramban if כי אב המון גוים נתתיך refers to the world (Rashi) or Klal Yisroel (Ramban.)  In Rashi's view, Avraham is the av for everyone.  He retains his mission of preaching to the world.  Accoridng to the Ramban, he is elevated above everyone else and is the father of his unique nation.