Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 49
Sanskrit:
इत्येतद् वर्णितं राजन् यन्न: प्रश्न: कृतस्त्वया ।यथा ब्रह्मण्यनिर्देश्ये निर्गुणेऽपि मनश्चरेत् ॥ ४९ ॥
ITRANS:
ity etad varṇitaṁ rājanyan naḥ praśnaḥ kṛtas tvayāyathā brahmaṇy anirdeśyenīṛguṇe ’pi manaś caret
Translation:
Thus I have replied to the question you asked me, O King, concerning how the mind can have access to the Absolute Truth, which is indescribable by material words and devoid of material qualities.