Sadhana Pada is the second chapter of Patanjali Yoga Sutra, where Patanjali comes down to the level of those who are not spiritually evolved. It is in this chapter that Maharshi Patanjali explains ways to aspire for the absolute freedom. In Sadhana Pada, he also elucidates the concept of Kriya Yoga. Kriya meaning action and Kriya Yoga, the yoga of action, has three tiers, namely tapas, svadhyaya and Isvarapranidhana. Tapas means burning desire, Savadhyaya means self study and Isvarapranidhana that means surrender to God.
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Sadhana Pada in Patanjali Yoga Sutra denotes the idea of practicing yoga that leads to spiritual illumination