Bhagavad Gita 6.8
He who desires nothing but wisdom and spiritual insight, who has conquered his senses, and who looks upon a lump of earth, a stone, and fine gold with the same eye, is a real saint.
ज्ञानविज्ञानतृप्तात्मा कूटस्थो विजितेन्द्रियः।
युक्त इत्युच्यते योगी समलोष्टाश्मकाञ्चनः॥jñānavijñānatṛptātmā kūṭastho vijitendriyaḥ|
yukta ityucyate yogī samaloṣṭāśmakāñcanaḥ||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).