Bhagavad Gita Chapter 18 Verse 33
धृृत्या, यया, धारयते, मनःप्राणेन्द्रियक्रियाः,
योगेन, अव्यभिचारिण्या, धृतिः, सा, पार्थ, सात्त्विकी।।33।।
Dhrtya, yya, dhaaryate, manHpraanendriyakriyaH,
Yogen, avyabhichaarinya, dhrtiH, saa, paarth, saatviki ||33||
Translation: (Paarth) of Paarth! (yya) which (avyabhichaarinya) unadulterous/undeviating/unwavering - based on one God (dhrtya) steadfastness, a person (yogen) through Bhakti-yog (manHpraanendriyakriyaH) activities of mind, breath and senses (dhaaryate) assumes/maintains/controls (saa) that (dhrtiH) steadfastness/patience (saatviki) is Satvik. (33)
Translation: Oh Paarth! The unwavering steadfastness in one God by which a person assumes the activities of mind, breath and senses through Bhakti-yog –that is Satvik steadfastness.