When he was eight years old, the Frierdiker Rebbe recorded the events of the previous Pesach in his diary:
Erev Pesach, after learning the Seder Korbon Pesach with me, my father said, “Tonight, Eliyahu Hanavi is coming to all the Jewish homes, and the great tzaddikim will merit to see him. Although all neshamos can see everything in heaven, when they are placed in a body, they can only feel it. Mishna has the same letters as neshama; therefore, now you should begin reviewing the Mishnayos of Tractate Pesachim eight times, and when you will come with me after bentshing to open the door for Eliyahu Hanavi, you should review the tractate a ninth time…”
(ספר המאמרים תשי”א ע’ 296)
