Bhagavad Gita 6.15
Thus, keeping his mind always in communion with Me and subduing his thoughts, he shall attain that Peace which is Mine and will lead him to liberation at last.
युञ्जन्नेवं सदाऽऽत्मानं योगी नियतमानसः।
शान्तिं निर्वाणपरमां मत्संस्थामधिगच्छति॥yuñjannevaṃ sadā''tmānaṃ yogī niyatamānasaḥ|
śāntiṃ nirvāṇaparamāṃ matsaṃsthāmadhigacchati||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).