योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-210, verse-21

यदेव ब्रह्मदेहोऽसौ स्वप्नाभः स्वप्न एष तु ।
त्वद्वोधायोच्यते युक्तिर्न तु तत्स्वप्न एव तु ॥ २१ ॥

yadeva brahmadeho'sau svapnābhaḥ svapna eṣa tu ,
tvadvodhāyocyate yuktirna tu tatsvapna eva tu 21

21. The body is a visionary appearance, and the great body of Brahma, is likened unto the figure of a phantom in vision, which represents the forms of all things as in dream in the stupendous fabric of the universe. [Brahma is more likely the phantasmagoria that shows all forms in it. Gloss].