BG 6.18
यदा विनियतं चित्तमात्मन्येवावतिष्ठते ।
निस्पृह: सर्वकामेभ्यो युक्त इत्युच्यते तदा ॥ १८ ॥
yadā viniyataṁ cittam
ātmany evāvatiṣṭhate
nispṛhaḥ sarva-kāmebhyo
yukta ity ucyate tadā
yadā — when; viniyatam — particularly disciplined; cittam — the mind and its activities; ātmani — in the Transcendence; eva — certainly; avatiṣṭhate — becomes situated; nispṛhaḥ — devoid of; sarva — all kinds of; kāmebhyaḥ — material desires; yuktaḥ — well situated in yoga; iti — thus; ucyate — is said to be; tadā — at that time.
When the yogī , by practice of yoga , disciplines his mental activities and becomes situated in Transcendence—devoid of all material desires—he is said to have attained yoga .
The activities of the yogī are distinguished from those of an ordinary person by his characteristic cessation from all kinds of material desires—of which sex is the chief. A perfect yogī is so well disciplined in the activities of the mind that he can no longer be disturbed by any kind of material desire. This perfectional stage can automatically be attained by persons in Kṛṣṇa consciousness, as is stated in the Śrīmad-Bhāgavatam ( 9.4.18 -20):
This transcendental stage may be inexpressible subjectively by the followers of the impersonalist path, but it becomes very easy and practical for a person in Kṛṣṇa consciousness, as is apparent in the above description of the engagements of Mahārāja Ambarīṣa. Unless the mind is fixed on the lotus feet of the Lord by constant remembrance, such transcendental engagements are not practical. In the devotional service of the Lord, therefore, these prescribed activities are called arcanā, or engaging all the senses in the service of the Lord. The senses and the mind require engagements. Simple abnegation is not practical. Therefore, for people in general—especially those who are not in the renounced order of life—transcendental engagement of the senses and the mind as described above is the perfect process for transcendental achievement, which is called yukta in the Bhagavad-gītā.