Menachem Mendel of Kotzk

“Do not be satisfied with the speech of your lips and the thought in your heart, all the promises and good sayings in your mouth, and all the good thoughts in your heart; rather you must arise and do!”

“When a man makes a reverent face before a face that is no face — that is idol worship!”

“If I am I because I am I, and you are you because you are you, then I am I and you are you. But if I am I because you are you and you are you because I am I, then I am not I and you are not you!”

“Everything must be done Lesheim Shamayim (for the sake of Heaven), even [actions done] Lesheim Shamayim.”

“God is only where you let Him in.”

“First, a man is created in his own image, and only afterwards in the image of God.”

“All that is thought should not be said, all that is said should not be written, all that is written should not be published, and all that is published should not be read.”

“People are accustomed to look at the heavens and to wonder what happens there. It would be better if they would look within themselves, to see what happens there.”