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प्रशान्तमनसं ह्येनं योगिनं सुखमुत्तमम् ।
उपैति शान्तरजसं ब्रह्मभूतमकल्मषम् ॥६- २७॥

prashaantamanasaM hyenaM yoginaM sukhamuttamam ।

upaiti shaantarajasaM brahmabhootamakalmaSham ॥६- २७॥

Source: Automatic ITRANS Transliteration

Indeed, this practitioner enjoys deep peace of mind, supreme happiness,
quench of ambition, faultless identification with the universe.

Source: Milind S. Pandit

Supreme bliss comes to a Self-realized yogi whose mind is tranquil, whose desires are under control, and who is free from sin (or faults).

Source: The Bhagavad-Gita: The Sacred Song

The yogi whose mind is fixed on Me verily attains the highest happiness. By virtue of his identity with Brahman, he is liberated; his mind is peaceful, his passions are quieted, and he is freed from sin.

Source: Bhagavad Gita As It Is