Bhagavad Gita 5.24
He who is happy within himself and has found its peace, and in whom the inner light shines, that sage attains eternal bliss and becomes one with the spirit.
योऽन्तःसुखोऽन्तरारामस्तथान्तर्ज्योतिरेव यः।
स योगी ब्रह्मनिर्वाणं ब्रह्मभूतोऽधिगच्छति॥yo'ntaḥsukho'ntarārāmastathāntarjyotireva yaḥ|
sa yogī brahmanirvāṇaṃ brahmabhūto'dhigacchati||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).