הרב בן בג בג

Ben Bag Bag was a tanna whose teachings appear across the Talmud in matters of korbanos, civil law, and Torah study. He is best known for his words in Pirkei Avot: “Turn it over and over, for everything is in it; gaze into it, grow old and worn in it, and do not stir from it, for you have no measure better than it” — a charge to immerse oneself wholly in Torah.

In the laws of the Temple service, he taught that the daily tamid offering requires inspection four days before its slaughter, deriving this from the verse “you shall guard to offer to Me at its appointed time” (Bamidbar) compared with the guarding of the Pesach lamb until the fourteenth day (Shemot). This teaching is brought in several places, including Pesachim, Menachot, and Arachin, where the Mishnah is identified as following his view. In Bechorot he applies a gezeirah shavah on the word “seh” (lamb) to exclude other animals.

He also appears in civil law: in Bava Kamma he holds that one may not enter a neighbor’s courtyard to retrieve his own property without permission, lest he appear as a thief, but rather should take it openly and declare it his — a view the Gemara notes is his alone, with the Sages disagreeing. In Eruvin he expounds the verses on what may be purchased with maaser-sheni money, learning that an item bought together with its container or covering (an animal with its hide, sheep with their wool, wine with its jug) is included. The Gemara in Kiddushin records that Yochanan ben Bag Bag sent to Rabbi Yehudah ben Beseira at Netzivin to inquire about whether a betrothed daughter of Israel may eat terumah.