The Bus in London
It is told that Rav Yehuda Zev once told a close talmid about the moment that changed the course of his childhood, speaking of it only after five decades had passed. He was eight years old and crossing a street in London when a city bus suddenly swerved toward him. The driver slammed on the brakes, and the bus stopped only inches from the boy.
Rav Yehuda Zev explained what went through his mind afterward. If a life can end in a single second, he realized, then we cannot possibly have been created just to enjoy the present moment. And such a great miracle, he felt, obliged him to devote himself to the service of Hashem.
From that day, the boy who had nearly been struck by a bus began to live with a different outlook, and it stayed with him for the rest of his life.