Bhagavad Gita 6.21
When he enjoys the bliss that surpasses the senses and can only be grasped by the pure intellect, when he comes to rest within his highest self, he will never again stray from reality.
सुखमात्यन्तिकं यत्तद्बुद्धिग्राह्यमतीन्द्रियम्।
वेत्ति यत्र न चैवायं स्थितश्चलति तत्त्वतः॥sukhamātyantikaṃ yattadbuddhigrāhyamatīndriyam|
vetti yatra na caivāyaṃ sthitaścalati tattvataḥ||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).