Ānanda (Ananda) is one of the Thousand names of God Viṣṇu (Vishnu). In several Purāṇa(s) (Purana; Mythological Scripture), Viṣṇu has been identified with the Supreme Brahman, and so the Ānanda-svarūpa (the blissful Self) of Brahman is also attributed to Viṣṇu. In his commentary on Viṣṇusahasranāma (Vishnusahasranama), citing the words of Vṛhadāraṇyaka Śruti (Vrihadaranyaka Sruti) Sankarācārya(Sankaracharya) has written — He is his the greatest manifestation of bliss. All creatures that have been born in this world, due to Avidya (the unreal knowledge), only partake of a small share of this Supreme bliss, and live on —
eṣo’sya parama ānandaḥ, etasyaivānandasya anyāni bhūtāni mātrām upajīvanti.