“When I was a little boy in Lubavitch,” said the Previous Rebbe, “I would often sit and stare out the window. My teacher, the Rashbatz, would give me guidance on how to change my nature. He would tell me: ‘Why must you be in the house looking outside [i.e., at the superficiality and foolishness of the material world]; instead go outside and look in through the window [at the inner, deeper perspective of life].’”

Sefer HaSichos 5696, p. 10