O son of Prtha, that determination which is unbreakable, which is sustained with steadfastness by yoga practice, and thus controls the mind, life, and the acts of the senses, is in the mode of goodness. BG 18.33 - 1972

Expressions researched:
"O son of Pṛthā, that determination which is unbreakable, which is sustained with steadfastness by yoga practice, and thus controls the mind, life, and the acts of the senses, is in the mode of goodness"

Bhagavad-gita As it is

BG Chapters 13 - 18

O son of Pṛthā, that determination which is unbreakable, which is sustained with steadfastness by yoga practice, and thus controls the mind, life, and the acts of the senses, is in the mode of goodness.

BG 18.33 (1972), Translation and Purport

O son of Pṛthā, that determination which is unbreakable, which is sustained with steadfastness by yoga practice, and thus controls the mind, life, and the acts of the senses, is in the mode of goodness.

Yoga is a means to understand the Supreme Soul. One who is steadily fixed in the Supreme Soul with determination, concentrating one's mind, life and sensual activities on the Supreme, engages in Kṛṣṇa consciousness. That sort of determination is in the mode of goodness. The word avyabhicāriṇya is very significant, for it refers to persons who are engaged in Kṛṣṇa consciousness and are never deviated by any other activity.