Bhagavad Gita 12.14

Always content, self-centered, self-controlled, resolute, with mind and reason dedicated to Me, such a devotee of Mine is beloved to Me.

सन्तुष्टः सततं योगी यतात्मा दृढनिश्चयः।मय्यर्पितमनोबुद्धिर्यो मद्भक्तः स मे प्रियः॥

santuṣṭaḥ satataṃ yogī yatātmā dṛḍhaniścayaḥ|mayyarpitamanobuddhiryo madbhaktaḥ sa me priyaḥ||

English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).