Following the previous episode concerning the angels, who is speaking to whom here?
Rashi and Ramban #1: Hashem is speaking to Avraham - carrying out his decision to reveal the impending destruction of Sedom to him.
Ramban #2 (al-Pi Kabalah): Hashem was saying it to Himself, as He 'descended' from Midas Rachamim to Midas ha'Din. 1
Seforno: Hashem is speaking to him, only whereas the earlier appearance was a mere revelation, now it was in the form of a prophecy.
Targum Yonasan: Hashem is speaking here to the angels. However the Ramban states that the commentaries agree unanimously that He is speaking to Avraham, as Rashi explains.
These cities saw how Avraham miraculously defeated the four kings. How could they do such terrible Aveiros?
Lev Eliyahu (Bereishis p.44): They were used to living based on their Midos and lusts, and did not follow intellect.
במשנה באבות כתוב "שלי שלי ושלך שלך הרי זו מידת סדום" משמע שהעמידו דבריהם על שורת הדין, ואילו בפסוק מבואר שהיו רשעים?