धृत्या यया धारयते मनःप्राणेन्द्रियक्रियाः।योगेनाव्यभिचारिण्या धृतिः सा पार्थ सात्त्विकी।।18.33।।
dhṛityā yayā dhārayate manaḥ-prāṇendriya-kriyāḥ yogenāvyabhichāriṇyā dhṛitiḥ sā pārtha sāttvikī
The unwavering firmness, through which Yoga restrains the functions of the mind, life-force, and senses—that firmness, O Arjuna, is Sattvic (pure).