Ālasya or laziness is the worst enemy of man. When even material well-being is blocked by it, how can the lazy one hope for spiritual progress? That is why Patañjali, the great teacher of Yoga, has listed it as an antarāya or obstacle in the path of yoga (vide Yogasūtras 1.30). Since it is caused by an excess of tamas (dark element among the guṇas), it is to be overcome by rajas (activity) and sattva (dynamic goodness).
Suśruta, the great teacher of Āyur-veda (Hindu system of medicine and surgery), considers ālasya as a condition which inclines a man more towards pleasure and less towards work, though capable (vide Suśruta Saṁhitā, Śārīrasthāna, 4.51).