Why does the Torah introduce the Parshah of Arayos with the words "Ani Hashem Elokeichem"?
Rashi 1 (citing the Sifra) and R. Bachye #1: It is a warning that, having accepted Hashem's Sovereignty, 1 we are now obligated to accept His decrees.
Rashi #2 and R. Bachye #2 (both citing Rebbi in the Sifra): With the advance knowledge that, in the time of Ezra, Yisrael would cast off the yoke of the sin of Arayos, Hashem reminded them here that it was He who issues the decrees and that He will judge and punish them, on the one hand, and that He can be relied upon to reward, on the other. 2
Ramban: It is a command to believe in Hashem and that He is the G-d of Yisrael. 3
Oznayim la'Torah: Because the Yeitzer ha'Ra of Giluy Arayos is the strongest desire that exists - as is evident from the fact that nit is the ponly sin that incorporates Yichud (a prohibition against seclusion). 6 It thererore serves as a reminder that Hashem sees and knows everything.
Sifra: 'I am Hashem who punished the Dor ha'Mabul, the people of S'dom and the Egyptians, and I will punish you if you follow in their footsteps!' 7
Rashi: When He declared "Anochi Hashem Elokecha" - Sh'mos, 20:2.
See Sifsei Chachamim.
This is how the Ramban explains the Mitzvah of "Anochi Hashem Elokecha" (Sh'mos 20:2), with which he equates the current Pasuk.
R. Bachye: As in Sh?mos 25:9 ?ke?Chol asher Ani Mar?eh oscha? and 15:26 ?ki Ani Hashem Rof?echa? - where it denotes Midas Rachamim). ? See R. Chavel?s footnotes.
R. Bachye
See Oznayim la'Torah.
See Torah Temimah, note 1.
How could Moshe say "Ani Hashem Elokeichem"?
Ramban: When Moshe left the presence of Hashem without the mask 1 and told Yisrael what Hashem had commanded him, it was self-understood that he was merely transmitting Hashem's words. 2
See the end of Ki Sisa.
And it was unnecessary to add "Koh Amar Hashem". Indeed, we find this format throughout Seifer Devarim - See for example the second Parshah of the Sh'ma (Devarim 13:15), where it was not Moshe, but Hashem, who sends the rain and causes the vegetation to grow (Ramban).
