He initially studied under the watch of
Rabban Gamliel of Yavne and senior of
Rabbi Akiva, and later took up residence in
Beit She'arim (Roman-era Jewish village). A great
halakist, always provided with satisfactory answers to all questions, he was familiarly called "pedler's basket" or "bundle of halakot"; the number and diversity of
halakot cited under his name in the
Mishnah alone, about 40, justify those titles. Besides exhaustive rabbinical knowledge, he acquired familiarity with the general science of his time, especially
geometry. It was said of him, as of his colleague R.
Eleazar Chisma, that he could approximately state the number of drops contained in the sea. Also like R. Eleazar Chisma, he was very poor. Through the influence of R.
Joshua ben Hananiah both were appointed by
Rabban Gamliel to remunerative offices. Rabbi Johanan showed himself grateful to Rabban Gamliel. When, after that patriarch's death, Rabbi Joshua proposed a change in a rule established by Rabban Gamliel, Rabbi Johanan opposed him: "I have observed that the head is always followed by the body; as long as Rabban Gamliel lived we observed the rule laid down by him, and now you propose to veto his directions. Joshua, we shall not listen to you". Close scholarly relations also existed between him and R.
Halafta. He was very pious, and therefore later rabbis said that when one dreams of Rabbi Johanan ben Nuri one may hope to develop a wholesome fear of sin. ==Teachings==