Yoga Sutras of Patanjali · 1.37

वीतरागविषयं वा चित्तम् ॥३७॥

vītarāgaviṣayaṁ vā cittam

Or, by taking as object the mind of one who is free from attachment.

— Yoga Sutras of Patanjali 1.37

Source: Sanskrit attributed to Patanjali (c. 2nd century BCE – 4th century CE). Public-domain English readings drawn from Swami Vivekananda's 'Raja Yoga' (1896) and Charles Johnston's 'The Yoga Sutras of Patanjali' (1912).