In 1885, the year that Rav Kook studied in the famed yeshivah of Volozhin, he was unanimously chosen to lead the Purim revelry as Purim gabbai. The most important students in the yeshivah lit the streetlights along the road from Rav Kook’s lodgings to the yeshivah. This created a festive atmosphere, as Rav Kook was led to the yeshivah and to the home of the Rosh Yeshivah, Rabbi Naftali Tvi Yehudah Berlin, known as the Netziv.
Efraim Teitelbaum, Rav Kook’s roommate, related that when the Rav reached the home of the Netziv, he recited the usual verses poking fun at the administration and at events that had occurred in the yeshivah. However, instead of composing his doggerel in the vernacular Yiddish, he did so in Hebrew and Aramaic.
One of his quips was, “Berlin will sink and Berlin will rise.” That is, the Haskalah of Berlin — the ‘Enlightenment’ movement that advocated integrating into European society — will sink, while the Torah of the Rosh Yeshivah, Rabbi Berlin, will rise. Several students in the yeshivah had studied the Haskalah literature and had been enticed by it. When they expressed their delight and amazement at the Rav’s mastery of Hebrew and Aramaic, the Netziv turned to them and remarked, ‘Not only does he excel in Torah and yirat shamayaim (piety), but even in this subject you do not reach his ankles.’
In delivering his Purim compositions, Rav Kook imitated the Netziv’s manner of speech and enunciation. But he was repaid in kind many years later by the great-grandson of the Netziv, Rabbi Yitzchak Charif, who was chosen to be the ‘Purim rabbi’ in Rav Kook’s own yeshiva, Yeshivat Mercaz HaRav.
Rabbi Yitzchak, having internalized every word that he had heard Rav Kook speak, proceeded to make a Purim speech in precise imitation of the Rav’s style and cadence. In his speech, he analyzed his position of ‘Purim rabbi'. Did it encompass only the rabbinate of Jerusalem, or did his nomination entitle him to officiate as the chief rabbi of all of Eretz Yisrael?
The scholarship and mental agility which he brought to his speech amazed all those present. Rav Kook was also impressed by Rabbi Yitzchak’s address. He admitted that he had been unaware of the scholar’s greatness in Torah. ‘Now I am getting my due,’ Rav Kook noted. ‘The great-grandson is repaying me here in Jerusalem for that which I said to his great- grandfather in Volozhin.’
("Celebration of the Soul” by R. Moshe Zvi Neriyah, translated by R. Pesach Jaffe, pp. 123-124.)