At the end of the millennium, the would-be Vaivasvata Manu, of the name Satyavrata, would see that the Lord in the fish incarnation is the shelter of all kinds of living entities, up to those in the earthly planets. Because of my fear of the vast water at the end of the millennium, the Vedas come out of my [Brahmā’s] mouth, and the Lord enjoys those vast waters and protects the Vedas.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
मत्स्यो युगान्तसमये मनुनोपलब्धः क्षोणीमयो निखिलजीवनिकायकेतः । विस्रंसितानुरुभये सलिले मुखान्मे आदाय तत्र विजहार ह वेदमार्गान्
matsyo yugāntasamaye manunopalabdhaḥ kṣoṇīmayo nikhilajīvanikāyaketaḥ | visraṃsitānurubhaye salile mukhānme ādāya tatra vijahāra ha vedamārgān
SB 2.7.12