The Yoga Sūtras, attributed to Patañjali and usually dated to the early centuries CE, are some 195 terse aphorisms in four chapters, on concentration, practice, powers and liberation. They set out the eight limbs of yoga and a psychology of the mind’s movements, afflictions and impressions, built on Sāṃkhya metaphysics. Vyāsa’s commentary is the oldest and most authoritative.
Yoga Sūtras
Patañjali’s classic aphorisms on yoga, defining it as the stilling of the movements of the mind.
Also: Yoga Sutras of Patanjali