Patanjali Yoga Sutra 4.7
Sanskrit Sutra
कर्माशुक्लाकृष्णं योगिनस्त्रिविधमितरेषाम्॥७॥
Swami Vivekananda's translation
Works are neither black nor white for the Yogis; for others they are threefold — black, white, and mixed.
Chapter link: Yoga Sutra Chapter 4

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