רבי אלעזר ברבי צדוק

Rabbi Elazar beRabbi Tzadok — Eliezer bar Tzadok in some texts — was a tanna and a kohen, son of Rabbi Tzadok, and his name appears many times in the Mishnah. He and his father were close to the house of the nasi, Rabban Gamliel, coming there often, and much of what is known about the conduct of that house rests on his testimony. He told that many times he went in after his father to Rabban Gamliel and saw that the room of the couches was not swept on Yom Tov: it was swept the day before and sheets were spread over the beds, so that when guests arrived and the sheets were lifted away the room turned out to have swept itself. He described as well how they perfumed the house on Yom Tov without setting spices on coals — pierced vessels were filled with fragrance before the festival and their holes stopped up, and on the day itself the holes were opened and the scent spread through the house. Later poskim weighed that testimony in discussing whether a man may fill an empty vessel with smoke and smell from it on Shabbat.

Several sources indicate that he and his father Rabbi Tzadok were kohanim, while another source points to the tribe of Binyamin. Tosafot settles the difficulty by saying that his father was a kohen and his mother of Binyamin; the version in the Yerushalmi in Masechet Taanit attaches the Binyaminite descent instead to Rabbi Eliezer beRabbi Yosi HaGelili.