Kriya — The Power of Right Action in the World
Kriya (action, from 'kri' — to do) in the Yoga Sutras context refers specifically to purifying action — action performed with full awareness and without ego-identification with the fruits — which transforms ordinary activity into yoga practice.
Patanjali's Kriya Yoga (sutra 2.1) — Tapas, Svadhyaya, and Ishvara Pranidhana — is distinct from mere action (karma) by its quality: it is action performed with awareness (Svadhyaya ensures the practitioner knows what they are doing and why), purifying intensity (Tapas ensures the practice has genuine transformative force), and without personal agenda for the fruits (Ishvara Pranidhana ensures the ego is not the destination of the effort). This transforms all ordinary activity — work, relationships, physical practice, study — into yogic practice. The distinction from the Bhagavad Gita's Karma Yoga (action without attachment to fruits) is subtle but real: where the Gita emphasizes release of fruits, the Yoga Sutras emphasizes the complete dedication of fruits to Ishvara — a positive orientation that not only releases personal grasping but actively channels the practice's energy toward the sacred.
Austerity, self-study, and surrender to Ishvara are the yoga of action.
Philosopher Harry Frankfurt's analysis of 'wholeheartedness' — the integration of all one's motivational capacities behind a single commitment — describes the psychological state that Kriya Yoga produces: rather than divided, conflicted motivation, the practice of Tapas-Svadhyaya-Ishvara Pranidhana aligns all of the practitioner's energies toward a single direction.
Yoga Sutras of Patanjali