Rabbi Moshe Chaim Luzzatto, also known as the RaMCHaL after his initials, is best known for his classical work on piety, Mesilas Yesharim (Path of the Just). This book is studied in all Yeshivos and is considered the finest such work ever written. Indeed, Rabbi Yisroel Salanter, founder of the Musar movement which stressed the study of such books on piety, said, “All the classical works of Musar demonstrate that man must fear God. The Mesilas Yesharim tells us how.”
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