At the beginning of Parashat Va’Era, Hashem comes to Moshe and tells him that he is not the first prophet of God. Hashem explains that there were three main prophets of Hashem before: Avraham, Yitzchak, and Yaakov. However, He then elaborates that He appeared to them as “Keil Shakai,” and that “UShemi Adoshem Lo Nodati Lahem,” “My name Adoshem I did not reveal to them.” Why is this change in name significant, and why was Moshe privy to this revelation?
The Midrash Aggadah explains that the name “Adoshem” refers to accountability and justice, as later used when referring to the Makkot, “VeYeide’u Mitzrayim Ki Ani Adoshem,” “And Egypt will know that I am Adoshem.” Here, Hashem explains to Moshe that he has heard the Jews’ pain and suffering, and will free them. Through the use of His name “Adoshem,” Hashem tells Moshe that Yetziat Mitzrayim and the Makkot will both serve as process of vengeance against the Egyptians.
However, Rashi (ibid. s.v. “Be’Keil Shakai”) believes that the name “Adoshem” connotes truth and justice. Hashem did not use this particular name in his conversations with the Avot because He had not yet fulfilled that which He had promised them-- to relieve the Jews of their affliction and take them to Eretz Yisrael. However, in Sefer Shemot, as Hashem is on the verge of fulfilling His promise to Avraham to take the Jews out of Egypt, God reveals Himself to Moshe as “Adoshem.”
Seforno (ibid.), in contrast, believes that “Keil Shakai” refers to God’s creation of the world, whereas, the name “Adoshem” refers to God when He alters the laws of nature on the Bnei Yisrael’s behalf. God never had the need to change nature for the forefathers; however, in Sefer Shemot, God had to intercede to ensure the continuation of Am Yisrael.
Ultimately, all of these opinions differ over one key feature: mainly, what the name ‘Adoshem’ represents. Midrash Aggadah believes that it refers to God’s attribute of justice, Rashi believes that it refers to the divine attribute of truth, and Seforno understands it as a God’s changing of the laws of nature. While each of these attributes is different, they are similar in that God never needed to actualize them before. Hashem never needed to change nature because the Avot did not need large miracles to initiate faith, nor did He need to use vengeance on their behalf, and He had not yet fulfilled his promise. In fact, the only time when God ever uses His name ‘Adoshem’ with the Avot is right before the Brit Bein HaBetarim, when He originally makes the promise to Avraham that He would eventually take the Bnei Yisrael out of Egypt (Da’at Zekenim BeReishit 16:7 s.v. “ViAcharei Chein”), as recorded in BeReishit 16:7, “Vayomer Eilav ‘Ani Hashem Asher Hotzeiticha MeiUr Kasdim’” “And he said to him: ‘I am Hashem who took you out of Ur Kasdim.’” This context unifies the approaches of the Midrash Rabbah, Seforno, and Rashi.