Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 31
Sanskrit:
सन्तुष्टो यर्हि वर्तेत ब्राह्मणो येन केनचित् ।अहीयमान: स्वद्धर्मात् स ह्यस्याखिलकामधुक् ॥ ३१ ॥
ITRANS:
santuṣṭo yarhi vartetabrāhmaṇo yena kenacitahīyamānaḥ svad dharmātsa hy asyākhila-kāma-dhuk
Translation:
When a brāhmaṇa is satisfied with whatever comes his way and does not fall away from his religious duties, those very religious principles become his desire cow, fulfilling all his wishes.