Amidah-Avot-Apter Rav
The 5th of Nisan is the Yahrtzeit of Rav Avraham Yehoshua Heshel of Apt, the Ohev Yisrael. The Apter was awakened by three knocks on his window. It was the Shamash who did this to some and worshipers in the early morning to services. The Rabbi felt an unusual enthusiasm and buoyancy, she dressed rapidly and strode over to the synagogue. He asked the Shamash, “When you knocked at my window, did you have in mind an idea of special holiness?”
“No,” answered the Shamash. “I am ignorant in ideas of holiness, but there is a tradition in my family which I have inherited from my father, that I recite the names of Abraham, Isaac, and Jacob when I knock three times.”
These words, pronounced with simple sincerity, suffice to bring down to this world enthusiasm with which to serve God. (Dor Dei’ah, page 230)