None of these descriptions of Lord Anantadeva are imaginary. They are all transcendentally blissful and full of actual knowledge. However, unless one hears them directly from a bona fide spiritual master in the line of disciplic succession, one cannot understand them. This knowledge is delivered to Nārada by Lord Brahmā, and the great saint Nārada, along with his companion, Tumburu, distributes it all over the universe. Sometimes the Supreme Personality of Godhead is described as Uttamaśloka, one who is praised by beautiful poetry. Nārada composes various poems to glorify Lord Ananta, and therefore the word saṁślokayām āsa (praised by selected poetry) is used in this verse.
The Vaiṣṇavas in the Gauḍīya-sampradāya belong to the disciplic succession stemming from Lord Brahmā. Lord Brahmā is the spiritual master of Nārada, Nārada is the spiritual master of Vyāsadeva, and Vyāsadeva wrote the Śrīmad-Bhāgavatam as a commentary on the Vedānta-sūtra. Therefore all devotees in the Gauḍīyasampradāya accept the activities of Lord Ananta related in the Śrīmad-Bhāgavatam as authentic, and they are thus benefited by going back home, back to Godhead. The contamination in the heart of a conditioned soul is like a huge accumulation of garbage created by the three modes of material nature, especially the modes of rajas (passion) and tamas (ignorance). This contamination becomes manifest in the form of lusty desires and greed for material possessions. As confirmed herein, unless one receives transcendental knowledge in disciplic succession, there is no question of his becoming purified of this contamination.