Lord Caitanya continued explaining to Sanātana Gosvāmīabout Lord Kṛṣṇa's avatāras, or incarnations, which are His expansions who come to the material creation. The word avatāra means "one who descends from the spiritual sky." In the spiritual sky there are innumerable Vaikuṇṭha planets, and from these planets the expansions of the Supreme Personality of Godhead come into this universe.
The first descent of the Supreme Personality of Godhead, from the expansion of Saṅkarṣaṇa, is the first puruṣa incarnation. It is stated in Śrīmad-Bhāgavatam (1.3.1) that when the Supreme Personality of Godhead descends as the first puruṣa incarnation of the material creation, He immediately manifests sixteen elementary energies. Known as Mahā-Viṣṇu, He lies within the Causal Ocean, and it is He who is the original incarnation in the material world. Śrīmad-Bhāgavatam 2.6.42 states that He is the Lord of time, nature, cause and effect, mind, ego, the five physical elements, the three modes of nature, the senses and the universal form. He is the independent master of all moving and nonmoving living beings in the material world,
The influence of material nature cannot reach beyond the Virajā, or Causal Ocean, as confirmed in Śrīmad-Bhāgavatam (2.9.10). Neither the modes of material nature (goodness, passion and ignorance) nor material time have any influence on the Vaikuṇṭha planets. On those planets the liberated associates of Kṛṣṇa live eternally, and they are worshiped by both the demigods and the demons.
Material nature acts in two capacities, as māyā and pradhāna. Māyā is the direct cause, and pradhāna refers to the elements of the material manifestation. When the first puruṣa-avatāra, Mahā-Viṣṇu, glances over material nature, material nature becomes agitated, and the puruṣa-avatāra thus impregnates matter with the living entities. Simply by the glance of Mahā-Viṣṇu, consciousness is created, and this consciousness is known as the mahat-tattva. The predominating Deity of the mahat-tattva is Vāsudeva. This created consciousness is then divided into three departmental activities according to the three guṇas, or modes of material nature. Consciousness in the mode of goodness is described in the Eleventh Canto of Śrīmad-Bhāgavatam. The predominating Deity of this mode is Aniruddha. Consciousness in the mode of passion produces intelligence, and the predominating Deity in this case is Pradyumna. He is the master of the senses. Consciousness in the mode of ignorance causes the production of ether (the sky) and the ear. The cosmic manifestation is a combination of all these modes, and in this way innumerable universes are created. No one can count the number of universes.
These innumerable universes are produced from the pores of Mahā-Viṣṇu's body. As innumerable atoms pass through the tiny holes in a screen, innumerable universes similarly emanate from the pores of Mahā-Viṣṇu's body. As He breathes out, innumerable universes are produced, and as He inhales, they are annihilated. All of the energies of Mahā-Viṣṇu are spiritual: they have nothing to do with the material energy. In the Brahma-saṁhitā (5.48) it is stated that the predominating deity of each universe, Brahmā, lives only during one breath of Mahā-Viṣṇu. Thus Mahā-Viṣṇu is the original Supersoul of all the universes and the master of all universes as well.
The second Viṣṇu incarnation, Garbhodakaśāyī Viṣṇu, enters each and every universe, spreads perspiration from His body and lies down on that water. From His navel grows the stem of a lotus flower, and on that lotus flower the first creature, Brahmā, is born. Within the stem of that lotus flower are the fourteen divisions of planetary systems, which are created by Brahmā. In the form Garbhodakaśāyī Viṣṇu, the Lord maintains each universe and tends to its needs. Although He is within each material universe, the influence of the material energy cannot touch Him. When it is required, this very same Viṣṇu takes the form of Lord Śiva and annihilates the cosmic creation. The three secondary incarnations—Brahmā, Viṣṇu and Śiva—are the predominating deities of the three modes of material nature. The master of the universe, however, is Garbhodakaśāyī Viṣṇu, who is worshiped as the Hiraṇyagarbha Supersoul. The Vedic hymns describe Him as having thousands of heads.
The third incarnation of Viṣṇu, Kṣīrodakaśāyī Viṣṇu, is the incarnation of the mode of goodness. He is also the Supersoul of all living entities, and He resides on the ocean of milk within the universe. Thus Caitanya Mahāprabhu described the puruṣa-avatāras.
Lord Caitanya next described the līlā-avatāras, or "pastime" avatāras, and of these the Lord pointed out that there is no limit. Still, He described some of them—for example, Matsya, Kūrma, Raghunātha, Nṛsiṁha, Vāmana and Varāha.
As far as the guṇa-avatāras, or qualitative incarnations of Viṣṇu, are concerned, they are three—Brahmā, Viṣṇu and Śiva. Brahmā is one of the living entities, but due to his devotional service he is very powerful. This primal living entity, master of the mode of material passion, is directly empowered by Garbhodakaśāyī Viṣṇu to create innumerable living organisms. In the Brahma-saṁhitā (5.49) Brahmā is likened to a valuable jewel influenced by the rays of the sun, and the Supreme Lord, Garbhodakaśāyī Viṣṇu, is likened to the sun. If in some kalpa there is no suitable living entity who can act in Brahmā’s capacity, Garbhodakaśāyī Viṣṇu Himself becomes Brahmā and acts accordingly.