Bhagavad Gita 14.11
When the light of knowledge gleams forth from all the gates of the body, then be sure that purity prevails.
सर्वद्वारेषु देहेऽस्मिन्प्रकाश उपजायते।ज्ञानं यदा तदा विद्याद्विवृद्धं सत्त्वमित्युत॥sarvadvāreṣu dehe'sminprakāśa upajāyate|jñānaṃ yadā tadā vidyādvivṛddhaṃ sattvamityuta||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).