KAṬHA UPANISHAD · 1.2.23

नायमात्मा प्रवचनेन लभ्यो
न मेधया न बहुना श्रुतेन ।
यमेवैष वृणुते तेन लभ्यः
तस्यैष आत्मा विवृणुते तनूꣳ स्वाम् ॥ २३॥

nāyamātmā pravacanena labhyo
na medhayā na bahunā śrutena ।
yamevaiṣa vṛṇute tena labhyaḥ
tasyaiṣa ātmā vivṛṇute tanūꣳ svām ॥ 23॥

The Self is not to be won by eloquent teaching, nor by brain power, nor by much learning: but only he whom this being chooses can win Him, for to him this Self bares His body.