यदा विनियतं चित्तमात्मन्येवावतिष्ठते | निःस्पृहः सर्वकामेभ्यो युक्त इत्युच्यते तदा || १८ ||
yadā viniyataṃ cittam ātmany evāvatiṣṭhate nihspṛhaḥ 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; niḥspṛhaḥ—desireless; sarva—for all; kāmebhyaḥ—material sense gratification; yuktaḥ—well situated in yoga; iti—thus; ucyate—is said; tadā—at that time.
“When the mind is thoroughly disciplined and established in the Self alone, free from longing for all objects of desire — then one is said to be united (yukta).”
This verse defines the state of yoga from the perspective of the mind. Two conditions are required: the mind must be firmly resting in the Self (ātmani avatiṣṭhate) and it must be free from desire for sense objects (niḥspṛhaḥ sarva-kāmebhyaḥ). These two are deeply related: desire is what pulls the mind out of its natural resting in the Self. When desire quiets, the mind returns to its home. When the mind rests in the Self, desires naturally diminish.
In meditation, the instruction is simple: when the mind wanders to a desire or a plan, gently return it to the Self — to the simple sense of 'I am' without any qualification. This repeated return is the discipline (viniyatam) that gradually establishes the mind in its true home.