Talmud in Chayei Sarah - Abraham's Yeshiva Attendance

§ Rav Safra said: The time for the afternoon prayer of Abraham begins from when the walls begin to blacken from shade. When the sun begins to descend from the middle of the sky, producing shadows on the walls, that marks the beginning of the setting of the sun and then the afternoon prayer may be recited. Rav Yosef said: And will we arise and derive a halakha from Abraham? Didn’t Abraham live before the Torah was given to the Jewish people, and therefore halakhot cannot be derived from his conduct? Rava said: The tanna derived a halakha from Abraham’s conduct, and we do not derive a halakha from his conduct? As it was taught in a baraita with regard to the verse: “And on the eighth day the flesh of his foreskin shall be circumcised” (Leviticus 12:3), this verse teaches that the entire day is suitable for performance of the mitzva of circumcision. However, the vigilant are early in their performance of mitzvot and circumcise in the morning, as it is stated with regard to the binding of Isaac: “And Abraham arose early in the morning and saddled his donkey” (Genesis 22:3). He awakened early to fulfill the mitzva without delay. Apparently, halakha is derived from the conduct of Abraham. Rather, Rava said: With regard to Rav Yosef, it was not the matter of deriving halakha from the conduct of Abraham that is difficult. Rather, this is difficult for him, as we learned in a mishna: When Passover eves occur on Shabbat eves, the daily afternoon offering is slaughtered at six and a half hours of the day and sacrificed on the altar at seven and a half hours. The afternoon offering was slaughtered as early as possible to enable all the Paschal lambs, which were slaughtered after the daily afternoon offering was sacrificed, to be slaughtered and roasted before sunset, so that no labor would be performed on Shabbat. Now, if indeed this halakha is derived from the conduct of Abraham, let us slaughter the offering even earlier, from when the walls begin to blacken, just after the end of the sixth hour of the day. Apparently, halakha is not derived from the conduct of Abraham. The Gemara rejects this: What is the difficulty?
Perhaps the walls of the Temple begin to blacken only at six and a half hours of the day because they are not perfectly aligned. The Temple walls were broad at the bottom and gradually narrowed as they reached the top; therefore, the upper part of the wall did not cast a shadow on the wall opposite it until six and a half hours of the day.
Or, alternatively, it is different with regard to Abraham because there was great knowledge of astronomy [itztagninut] in his heart. He was able to precisely calculate the movements of the heavenly bodies and was therefore able to discern immediately after noon that the sun had begun its descent. Others require a half hour to be certain that the descent of the sun has begun.
Or, alternatively Abraham was different because he was an Elder and sat and studied Torah in a yeshiva, where the Divine Presence rests. There he developed the expertise to determine the precise hour. As Rabbi Ḥama, son of Rabbi Ḥanina, said: From the days of our ancestors, yeshiva never left them. Our ancestors were leaders of their generations, who taught Torah to students who came to them. When they were in Egypt there was a yeshiva with them, as it is stated: “Go and gather the Elders of Israel” (Exodus 3:16), indicating that there were Sages among them who studied Torah. And similarly, when they were in the desert, there was a yeshiva with them, as it is stated: “Gather for me seventy men from the Elders of Israel” (Numbers 11:16). Abraham our Patriarch was himself an Elder and would sit in yeshiva, as it is stated: “And Abraham was old, advanced in years” (Genesis 24:1). From the apparent redundancy of the terms old and advanced in years, it is derived that old means that he was a wise Elder and prominent in Torah, and advanced in years means that he was elderly. Similarly, Isaac our Patriarch was an Elder and sat in yeshiva, as it is stated: “And it came to pass when Isaac was old and his eyes were dim” (Genesis 27:1). Similarly, Jacob our Patriarch was an Elder and sat in yeshiva, as it is stated: “And Israel’s eyes were heavy with age” (Genesis 48:10). Eliezer, servant of Abraham, was an Elder and sat in yeshiva, as it is stated: “And Abraham said to his servant, the elder of his household, who ruled over all he had” (Genesis 24:2). Rabbi Elazar said: The verse means that he had mastery over the Torah of his master, having gained proficiency in all of the Torah of Abraham. That is the meaning of the verse: “He is Damascus [Dammesek] Eliezer” (Genesis 15:2). Rabbi Elazar said: The word Dammesek is a contraction of he who draws [doleh] and gives drink [mashke] to others from his master’s Torah. Apropos the previous statement, the Gemara cites that Rav said: Abraham our Patriarch fulfilled the entire Torah before it was given, as it is stated: “Because [ekev] Abraham hearkened to My voice and kept My charge, My mitzvot, My statutes and My Torahs” (Genesis 26:5). Rav Shimi bar Ḥiyya said to Rav: And say that the verse means that he fulfilled only the seven Noahide mitzvot and not the entire Torah. The Gemara asks: But isn’t there also circumcision that Abraham clearly observed, which is not one of the Noahide laws? Apparently, Abraham fulfilled more than just those seven. The Gemara asks: And say that he fulfilled only the seven mitzvot and circumcision. Rav said to him: If so, why do I need the continuation of the verse, that Abraham kept: My mitzvot and My Torah? That is a clear indication that he fulfilled mitzvot beyond the seven Noahide mitzvot, and apparently fulfilled the entire Torah. Rav said, and some say Rav Ashi said: Abraham our Patriarch fulfilled the entire Torah, even the mitzva of the joining of cooked foods, a rabbinic ordinance instituted later, as it is stated: My Torahs. Since the term is in the plural, it indicates that Abraham kept two Torahs; one, the Written Torah, and one, the Oral Torah. In the course of fulfilling the Oral Torah, he fulfilled all the details and parameters included therein.