Sources: Israel Salanter, Or Yisrael; Simcha Zissel Ziv, Chokhmah u-Mussar; Naftali Amsterdam, Netivot Or; Dov Katz, Tenuat HaMusar (historical study).

The Musar movement (~1840 AD) is an ethical-pietistic movement within Lithuanian (Litvish) Orthodox Judaism, founded by Rabbi Israel Lipkin Salanter (~1809–1883 AD). Salanter’s diagnosis: the Lithuanian Jewish world had produced extraordinary Talmudic scholars who were often ethically underdeveloped — brilliant in legal analysis, deficient in character. His prescription: systematic ethical self-examination and psychological self-awareness, including the study of medieval ethical texts (Mesillat Yesharim, Chovot HaLevavot) and introspective exercises to identify and correct character flaws. The Musar yeshivot developed distinctive practices: (1) The Musar shtibl — a room in the yeshiva for private ethical meditation, often in dim light and to a particular melody to engage the emotions; (2) Mussar vaad — group sessions for ethical accountability; (3) Focus on specific midot (character traits) — working on one trait at a time (humility, truth, zeal, order). Three major Musar yeshivot developed distinct approaches: Kelm (systematic, intellectual), Slabodka (emphasizing human dignity — gedlut ha’adam), and Novardok (emphasizing self-abnegation and breaking the ego). The movement shaped Lithuanian Orthodox Jewish culture and influenced modern Orthodox Jewish ethical education. Holocaust survivor Eliyahu Eliezer Dessler’s Michtav MeEliyahu synthesized Musar with broader spiritual concerns.