Srimad-Bhagavatam: Canto 6 - Chapter 1 - Verse 21

Sanskrit:

वचस्युपरतेऽप्राप्य य एको मनसा सह ।अनामरूपश्चिन्मात्र: सोऽव्यान्न: सदसत्पर: ॥ २१ ॥

ITRANS:

vacasy uparate ’prāpyaya eko manasā sahaanāma-rūpaś cin-mātraḥso ’vyān naḥ sad-asat-paraḥ

Translation:

The words and mind of the conditioned soul cannot approach the Supreme Personality of Godhead, for material names and forms are not applicable to the Lord, who is entirely spiritual, beyond the conception of gross and subtle forms. The impersonal Brahman is another of His forms. May He, by His pleasure, protect us.

Purport:

The impersonal Brahman, which is the effulgence of the Lord, is described in this verse.