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jñānena tu tad ajñānam yeṣāṃ nāśitam ātmanaḥ | teṣām ādityavaj jñānaṃ prakāśayati tat param
“As the sun dispels darkness and illuminates everything, so divine knowledge destroys ignorance and reveals the transcendental Absolute Truth.” — Bhagavad-Gītā 5.16    

The incarnations of God

It unfortunately happens again and again that persons call themselves Avatāras or are praised as such by their followers, although they are ordinary people. The ignorance and audacity even goes so far as to use the term avatāra for a particular internet technology.

Avatāra means "one who has descended" and denotes an incarnation of God. The Supreme Lord appears in this world at different times for different purposes in different forms. Kṛṣṇadasa Kaviraja Gosvami, in the Caitanya-caritāmṛta, defines this term as follows:

An Avatāra, an incarnation of God, descends from the kingdom of God to manifest in the material world. And this form of the Personality of Godhead descending is called an incarnation or Avatāra. Such incarnations are inhabitants of the spiritual world, the kingdom of God, and when they descend into the material creation, they are called Avatāra.
— Caitanya-caritāmṛta, Madhya-līlā 20.263-264

How does one recognise an Avatāra? He is recognised by his superhuman miraculous deeds and in relation to the revealed scriptures. A true Avatāra does not claim to be an Avatāra. An ordinary person with a few extraordinary abilities should not allow himself to be worshipped as an Avatāra by fools who do not know the Śāstras.

Śrīmad-Bhāgavatam (1.3.26) states:

avatāra hy asankhyeya hareh sattva-nidher dvijah | yathavidasinah kulyah sarasah syuh sahasrasah
“O Brahmaṇas, the incarnations of Hari, the Personality of Godhead, the Ocean of Goodness, are innumerable, like rivers flowing from an inexhaustible reservoir of water.”
— Śrīmad-Bhāgavatam 1.3.26

Just as there are innumerable universes and innumerable waves in the ocean, so are the incarnations of God innumerable.

The Vedic scriptures describe different types of Avatāras. Six types are:

(1) Puruṣa-Avatāras,

(2) Guṇa-Avatāras,

(3) Līlā-Avatāras,

(4) Yuga-Avatāras,

(5) Śaktyavesa-Avatāras,

(6) Manvantara-Avatāras

(1) Puruṣa-Avatāras – Viṣṇu incarnations (Mahā Viṣṇu, Garbhodakaśāyī Viṣṇu, Kṣīrodakaśāyī Viṣṇu). Mahā Viṣṇu is a complete expansion of an expansion of the primordial Lord. It is a gigantic form from whose pores all universes emerge in seed form when He exhales and into which they re-enter when He inhales. He lies on His serpent bed Ananta-śeṣa in the ocean of causes between the eternal spiritual realm and the material world. He expands into Garbhodakaśāyī Viṣṇu and enters into every universe as the sustainer. As Kṣīrodakaśāyī Viṣṇu, he is paramātmā (the Supersoul) in every living being. In the Satvata-tantra it is said:

"Viṣṇu has three forms called puruṣas. The first form, Mahā-Viṣṇu, is the creator of all material energy (mahat-tattva), the second form is Garbhodakaśāyī, who is situated in every universe, and the third form is Kṣīrodakaśāyī, who dwells in the heart of every living being.”

(2) Guṇa-Avatāras – incarnations of the modes of material nature (Brahmā, Viṣṇu, Śiva). Brahmā rules rajo-guṇa (creation), Viṣṇu sattva-guṇa (preservation) and Śiva tamo-guṇa (annihilation).

(3) Līlā-Avatāras – incarnations performing miraculous transcendental deeds (e.g. Kurma, Matsya, Varāha, Nṛsiṃha, Vāmana, Rāmacandra, Kṛṣṇa, Buddha, Kalki). In various Vedic scriptures, 25 Līlā-Avatāras are described. Some of these Avatāras are also called Kalpa-Avatāras because they appear once every kalpa (one day in the life of Brahma = 4,320,000,000 years).

(4) Yuga-Avatāras – incarnations that appear in each age to establish the respective yuga-dharma. In the satya-yuga, the Lord appears in a four-armed form with a white complexion, clad in an antelope skin, etc., and teaches meditation and religious principles. In the treta-yuga he appears in a four-armed form with a reddish complexion and teaches the performance of great sacrifices as yuga-dharma. In the dvāpara-yuga he appears in a blackish complexion, clad in yellow robes and adorned with the Kaustubha jewel and teaches the worship of the lotus feet of Kṛṣṇa as the yuga-dharma. In the kali-yuga he appears once in a kalpa with a yellowish or golden complexion and, as a devotee of the Lord, teaches kṛṣṇa-nāma-saṅkīrtana, the congregational chanting of the mahā-mantra as the religious process by which all living beings can attain love of God and liberation. Śrī Kṛṣṇa, the Supreme Lord, appeared in Navadvipa, Bengal, about 500 years ago as Śrī Kṛṣṇa Caitanya and established the saṅkīrtana-yajña as the yuga-dharma for this age.

In Caitanya-Caritāmṛta, Madhya-līla, Ch. 20, the Supreme Lord instructs His devotee Sanātana Goswami about His innumerable incarnations. Here follows an excerpt.

“O Sanatana, now hear from Me about the yuga-avataras, the incarnations for the millenniums. First of all, there are four yugas – Satya-yuga, Treta-yuga, Dvapara-yuga and Kali-yuga.

“In the four yugas – Satya, Treta, Dvapara and Kali – the Lord incarnates in four colors: white, red, black and yellow respectively. These are the colors of the incarnations in different millenniums.

“'This child formerly had three colors according to the prescribed color for different millenniums. Formerly He was white, red and yellow, and now He has assumed a blackish color.'

“'In the Satya-yuga, the Lord appeared in a body colored white with four arms and matted hair. He wore tree bark and bore a black antelope skin. He wore a sacred thread and a garland of rudraksa beads. He carried a rod and a waterpot, and He was a brahmacari.'

“'In the Treta-yuga, the Lord appeared in a body that had a reddish hue and four arms. There were three distinctive lines on His abdomen, and His hair was golden. His form manifested the Vedic knowledge, and He bore the symbols of a sacrificial spoon, ladle and so on.'

“As the white incarnation, the Lord taught religion and meditation. He offered benedictions to Kardama Muni, and in this way He showed His causeless mercy.

“In the Satya-yuga the people were generally advanced in spiritual knowledge and could meditate upon Krishna very easily. The people's occupational duty in Treta-yuga was to perform great sacrifices. This was induced by the Personality of Godhead in His reddish incarnation.

“In Dvapara-yuga the people's occupational duty was to worship the lotus feet of Krishna. Therefore Lord Krishna, appearing in a blackish body, personally induced people to worship Him.

“'In the Dvapara-yuga the Personality of Godhead appears in a blackish hue. He is dressed in yellow, He holds His own weapons, and He is decorated with the Kaustubha jewel and marks of Srivatsa. That is how His symptoms are described.'

“'I offer my respectful obeisances unto the Supreme Personality of Godhead, expanded as Vasudeva, Sankarsana, Pradyumna and Aniruddha.'

“By this mantra, the people worship Lord Krishna in the Dvapara-yuga.

“In the Kali-yuga the occupational duty of the people is to chant congregationally the holy name of Krishna.

“Accompanied by His personal devotees, Lord Krishna, assuming a golden color, introduces the hari-nama-sankirtana, the chanting of the Hare Krishna mantra, in the Age of Kali. By this process, He delivers love for Krishna to the general populace.

“Sri Krishna, the son of Nanda Maharaja, personally introduces the religion of the Kali Age. He himself sings and dances in ecstatic love, and so the whole world sings together.”

“'Those who are advanced and highly qualified and are interested in the essence of life, know the good qualities of Kali-yuga. Such people worship the Age of Kali because in this age, simply by chanting the Hare Krishna mahamantra, one can advance in spiritual knowledge and attain life's goal.'

“As stated before when I described the incarnations of the material modes [guna-avataras], one should consider that these incarnations also are unlimited and that no one can count them.”

(5) Śaktyavesa-Avatāras – beings endowed or empowered with special divine powers (e.g. Dhanvantari, Kapiladeva, Vedavyāsa, Narada, Buddha, Paraśurāma).

(6) Manvantara-Avatāras – Manu incarnations. In one day of Brahmā (4,320,000,000 years – Brahmā's night lasts the same length of time) 14 Manus appear and during his life 504,000 appear in one universe. There are innumerable universes and all universes exist for only one breath of Mahā-Viṣṇu. Mahā-Viṣṇu's breaths are unlimited. As onr can see, it is impossible to write in detail even about the Manu incarnations, what to speak of the other incarnations.

All Avatāras except Mahā-Viṣṇu, from whose pores innumerable universes emerge, appear in every universe, and not even Ananta-śeṣa, who carries the universes on his innumerable hoods and with his innumerable mouths constantly sings of the glories of Hari, the Supreme Lord, and his transcendental deeds in the spiritual and material worlds, is capable of describing them all.