Yoga-kṛtya (योककृत्य) — Vyāsa on Sense-Restraint, Obstacles, and Brahman-Realization
त्रेतायां संहता वेदा यज्ञा वर्णाश्रमास्तथा । संरोधादायुषस्त्वेते भ्रश्यन्ते द्वापरे युगे,त्रेतायुगमें वेद, यज्ञ और वर्णाश्रम-धर्म सुव्यवस्थितरूपसे पालित होते थे; परंतु द्वापरयुगमें आयुकी न्यूनता होनेसे लोगोंमें उनके पालनका उत्साह कम हो गया--वे वेद यज्ञ आदिसे च्युत होने लगे
tretāyāṃ saṃhatā vedā yajñā varṇāśramās tathā | saṃrodhād āyuṣas tv ete bhraśyante dvāpare yuge ||
Disse Vyāsa: Na era de Tretā, os Vedas eram preservados como um todo indiviso, e também os sacrifícios e as disciplinas das ordens sociais e espirituais (varṇa e āśrama) eram devidamente mantidos. Mas na era de Dvāpara, porque a duração da vida humana se torna limitada, essas instituições começam a declinar—e as pessoas, pouco a pouco, afastam-se dos Vedas, do sacrifício e dos deveres de varṇa e āśrama.
व्यास उवाच
As the yugas progress, human capacity—especially lifespan and steadiness—diminishes, and with it the ability to preserve Vedic learning, sacrificial discipline, and varṇāśrama duties; dharma declines not merely by doctrine but by weakened human endurance and commitment.
Vyāsa is explaining a yuga-based account of social and religious change: in Tretā, Vedic and ritual order is stable and well-observed; by Dvāpara, due to curtailed lifespan, people lose vigor for sustained observance, and established institutions begin to erode.