Why does it say "va'Ydaber Elokim El Moshe"?
Rashi: Hashem spoke to him with Mishpat (Midas ha'Din), because Moshe spoke harshly to Him and asked why He did evil to Yisrael.
Rashi writes that Hashem spoke to Moshe with Mishpat,, for Moshe asked Him why He did evil to Yisrael. If so, why did He inform him that His Name is Havayah?
Rashi: Because Havayah is also the Name that denotes that Hashem is faithful to reward those who go in His ways 1 and to punish those who rebel against Him.
Da'as Zekenim (verse 3): Even though I said that you are Elohim to Pharaoh, I am Hashem also for you.
Consequently, He did not send Moshe in vain, but to carry out the promise that He had made to the Avos (who went in His ways) that He would redeem their children (Rashi).
Rashi writes that Hashem spoke to Moshe with Mishpat. What is the source to say so?
Mizrachi (1st answer): Elokim means judge. It is also Midas ha'Din.
Da'as Zekenim, Moshav Zekenim and Mizrachi (2), from Makos 11a: "Va'Ydaber" connotes harsh 1 speech.
Ta'anis (30b): Until Dor ha'Midbar died out (like was decreed after the Meraglim), Hashem's Dibur was not Misyached with Moshe. Rashi (Devarim 2:16) - i.e. it does not say va'Ydaber, an expression of Chibah (endearment)! Moshav Zekenim - only va'Ydaber Elokim is harsh. Bartenura (32:7) - when it says "va'Ydaber... Leimor", it is not harsh. Kli Yakar (Devarim 2:16) - va'Ydaber is harsh rebuke. Hashem rebukes one whom He loves (Mishlei 3:12).
Rashi writes that here, Shem Havayah alludes to faithfulness to reward. He should say that it refers to faithfulness to punish, for it is written near Elokim (Mishpat)!
Moshav Zekenim: "Va'Yomer Elav" separates Shem Havayah from Elokim.
Moshav Zekenim: Va'Yomer is an expression of Chibah (endearment).