Biography
Yoezer Ish HaBirah was a tanna, counted among the disciples of Beit Shammai. He appears in the Mishnah in tractate Orlah, where he is identified by this affiliation and brings a halachic teaching he received firsthand.
In that passage he relates that he posed a question to Rabban Gamliel the Elder, whom he found standing at the eastern gate, and reports the answer he was given concerning when leaven becomes forbidden — that it does not render a mixture prohibited until there is enough of it to cause fermentation. His account preserves a direct exchange between a student of Beit Shammai and Rabban Gamliel the Elder.
יועזר איש הבירה היה תנא מתלמידי בית שמאי, חי במאה הראשונה לספירה בארץ ישראל. מוזכר פעם אחת במשנה במסכת ערלה.
On Wikipedia: עברית — summary from Wikipedia, CC BY-SA