Yōga Sūtra 1.33

मैत्रीकरुणामुदितोपेक्षाणां सुखदुःखपुण्यापुण्यविषयाणां भावनातश्चित्तप्रसादनम्।

maitrīkaruṇāmuditōpēkṣāṇāṁ sukhaduḥkhapuṇyāpuṇyaviṣayāṇāṁ bhāvanātaścittaprasādanam।

[मैत्री करुणा मुदित उपेक्षाणां सुख दुःख पुण्य अपुण्य विषयाणां भावन अतः चित्त प्रसादनम्।
maitrī = friendship; karuṇā = kindness; mudita = joy; upēkṣāṇāṁ = indifference to; sukha = pleasure; duḥkha = pain; puṇya = deeds resulting in good; apuṇya = deeds not resulting in good; viṣayāṇāṁ = on these topics; bhāvana ataḥ = cultivating the attitude of; citta = the consciousness; prasādanam = becomes serene;]

Cultivate the attitude of friendship towards those who are happy, kindness towards those who are in misery, joy towards those who are benevolent, and indifference towards those who are evil. From it, the Chitta becomes serene.

The positive qualities to be cultivated by practitioner are friendship, kindness, and joy. Along with-it practitioner should remain indifferent, i.e., develop equanimity towards pleasure and pain. Indifference is advocated toward good and not-good deeds as well, because any action with self-motive needs to be avoided. All this will aid to calm the mind and to prevent disturbances.