Editing Yoel Kahan (section)

==== As Mashpia and Educator ====
Shortly after his arrival at 770, he was appointed as a teacher of Chassidus, initially at the yeshiva in Bedford and Dean and afterwards at the yeshiva at 770. At the beginning of the year 5714 (1953-1954), they arranged a new Chassidus class in the yeshiva and looked for a Chassidus supervisor. Several suggestions were proposed to the Rebbe, and the Rebbe asked: "Why not Yoel? He would be suitable for this." In his holy response from 7 Adar 5747 (1987), the Rebbe wrote about him: "This is not about 'those who sit at street corners' but rather '''exactly the opposite'''... and this person educates in '''Chassidus''' (including in Tomchei Tmimim) for decades, etc."
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Rabbi Yoel served as the head mashpia in the central Tomchei Tmimim Yeshiva - 770, gave classes in 770 and farbrenged with the Kvutza students, and also participated in some of the administration meetings and would occasionally express his opinion on matters of yeshiva management. In the many farbrengens among Chabad Chassidim (and especially among the students), he would mainly emphasize the need for hiskashrus (connection) to the Rebbe.

For many years, he gave classes in Monsey and Lakewood, through which thousands became closer to Chabad Chassidus. As part of this, he gave a weekly class at the Chabad synagogue "Beis Menachem" on 16th Avenue in Boro Park. Occasionally, he would go on journeys to spread Chassidus in the United States, Europe, and the Holy Land, during which he gave many Chassidus classes to audiences of Polish Chassidim.

Among his distinguished students are the cream of Chabad mashpiim and rabbis, including: Rabbi Shlomo Zarchi, Rabbi Leibel Shapiro, Rabbi Nachman Shapiro, Rabbi Mendel Vechter, Rabbi Elimelech Zweibel, and others.