The phrase Torah im Derech Eretz is first found in the Mishna in Tractate Avoth (2:2): "Beautiful is the study of Torah with derech eretz, as involvement with both makes one forget sin". The term derech eretz, literally "the way of the land", is inherently ambiguous, with a wide range of meanings in Rabbinic literature, referring to earning a livelihood and behaving appropriately, among others.
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