Menachot 40a Wisdom and Knowledge - אם אתה יכול לקיים את שניהם מוטב

From Matmonim: Daf Yomi by Rabbi David Lapin by R David Lapin.

For knowledge one needs a good mind; for wisdom one needs a pure soul. Our actions purify or contaminate our souls. This is the meaning of yir’at cheit – fear of sin. 

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