Patanjali Yoga Sutra 2.1
Sanskrit Sutra
तपः-स्वाध्यायेश्वरप्रणिधानानि क्रियायोगः॥१॥
Swami Vivekananda's translation
Mortification, study, and surrendering fruits of work to God are called Kriyā-Yoga.
Vyasa Bhashya (Sanskrit)
उद्दिष्टः समाहितचित्तस्य योगः। कथं व्युत्थितचित्तोऽपि योगयुक्तः स्यादित्येतदारभ्यते –
तपःस्वाध्यायेश्वरप्रणिधानानि क्रियायोगः ॥ १ ॥
नातपस्विनो योगः सिध्यति। अनादिकर्मक्लेशवासनाचित्रा प्रत्युपस्थितविषयजाला चाशुद्धिर्नान्तरेण तपः संभेदमापद्यत इति तपस उपादानम्। तच्च चित्तप्रसादनमबाधमानमनेनाऽऽसेव्यमिति मन्यते। स्वाध्यायः प्रणवादिपवित्राणां जपो मोक्षशास्त्राध्ययनं वा। ईश्वरप्रणिधानं सर्वक्रियाणां परमगुरावर्पणं तत्फलसंन्यासो वा ॥ १ ॥
Vyasa Bhashya (English Translation)
Yoga for the concentrated mind has been declared (in Chapter 1). Now, how can even a distracted (vyutthita) mind become established in yoga? For this, it is begun: Austerity (tapas), study (svadhyaya), and devotion to Ishvara (Ishvara-pranidhana) constitute Kriya Yoga (the yoga of action). || 1 || Without austerity (tapas), yoga does not succeed. The impurity (ashuddhi)—which is variegated from beginningless actions (karma), afflictions (kleshas) and latent impressions (vasanas), and which is a net of present sense objects—is not broken up without austerity. Therefore, austerity is taken up. And it is thought that it should be practiced in a way that does not disturb the clarity (prasadana) of the mind. Study (svadhyaya) is the repetition of purifying mantras like Om (Pranava) or the study of scriptures on liberation (moksha-shastras). Devotion to Ishvara (Ishvara-pranidhana) is the offering of all actions to the Supreme Guru, or the renunciation of their fruits. || 1 ||
Chapter link: Yoga Sutra Chapter 2

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