Chapter-1, Sutra13

Patanjali Yogasutra 1.13 

(abhyas)

तत्र स्थितौ यत्नोऽभ्यासः ॥ १.१३॥

"There (in the state of having a controlled and tranquil mind), the effort to remain steady is practice."

The word 'there' refers to the state of nirodha or cessation of the fluctuations of the mind, which is the goal of yoga. This state is also called samadhi or absorption in the Self.

The word 'effort' implies a continuous and persistent attempt to maintain this state of nirodha, without being distracted by the external or internal stimuli that may cause the mind to waver.

The word 'practice' denotes the repeated and regular performance of the means to achieve nirodha, such as yama, niyama, asana, pranayama, pratyahara, dharana, dhyana, and samadhi. These are the eight limbs of yoga as described by Patanjali in his sutras.

The Sutra implies that the practice of yoga is not a one-time event, but a lifelong process that requires constant vigilance and discipline. The practice of yoga is not only a means to an end, but also an end in itself, as it leads to the Realization of one's True Nature.

Similar verses from Vedic texts, are:

Bhagavad Gita 6.35:

अभ्यासेन तु कौन्तेय वैराग्येण च गृह्यते ॥ ६.३५॥

"But by practice, O son of Kunti, and by detachment, it is attained."

This verse is spoken by Lord Krishna to Arjuna, when Arjuna expresses his doubt about the possibility of controlling the restless mind. Krishna assures him that by constant practice of yoga and by renouncing the attachment to the objects of the senses, one can master the mind and attain the state of nirodha.

Yogavashishta 2.18.18:

अभ्यासाद्धी तु तद्वृत्तिर्निरोधो निर्विकल्पकः ॥ १८॥

"By practice alone, the roaming mind is restrained naturally."

This verse is spoken by Sage Vasistha to Prince Rama, when he explains the nature and method of abhyasa or practice. Vasistha says that by practice alone, one can overcome the tendencies of the mind to create various thoughts and images, and attain the state of nirodha, which is free from any mental construct.