רבי אליעזר בן יעקב

Rabbi Eleazar ben Yaakov, also written Eliezer ben Yaakov, was a tanna of the first century who lived in the last days of the second Beit HaMikdash and in the generation after the churban. He saw the Beit HaMikdash with his own eyes — his uncle, his mother’s brother, was a Levi who served there — and he stands apart among the Tannaim for his many teachings about its structure and avodah: the exact place of the duchan on which the Leviim stood in song, the copper doors of Shaar Nikanor, and Roman soldiers who converted on erev Pesach and joined in the korban Pesach that same day. The Gemara concludes that he is the tanna who taught Masechet Middot, the masechta that describes the Beit HaMikdash chamber by chamber; of one lishkah he says simply, “I have forgotten what it served.”

Shimon ben Azzai told that he found a genealogical scroll in Yerushalayim in which was written that the mishnah of Rabbi Eliezer ben Yaakov is “kav v’naki” — small in measure and clean of flaw. On the strength of this the poskim give his opinion special weight, some ruling like him even against the many; some explain “kav” as gematria, one hundred and two, the number of his halachic statements in the Mishnah and the Bavli. He taught halachot of bikkurim, of kilayim in a vineyard, of the mikveh, and of the shirah of the Leviim; among his sayings: one who does a single mitzvah acquires for himself a single defender, and one who commits a single aveirah acquires a single accuser — teshuvah and maasim tovim are a shield before punishment.

A tradition from the fourteenth century places his kever near Kfar Chananya in the Galil (Israel), beside the kevarim of Rabbi Chalafta and his sons Rabbi Yosi and Rabbi Shimon.