Varaha Purana 2.21

गतकल्पावसाने तु निशि सुप्तोत्थितः शुभे । सत्त्वोद्रिक्तस्तथा ब्रह्मा शून्यं लोकमवैक्षत ॥ २.२१ ॥

gatakalpāvasāne tu niśi suptotthitaḥ śubhe | sattvodriktaḥ tathā brahmā śūnyaṁ lokam avaikṣata || 2.21 ||

At the close of the past kalpa, O auspicious one, Brahmā—awakened from sleep in the night and with sattva predominant—beheld the world as void.