There are six kinds of incarnations:

1) the purusha avatars
2) the lila avatars
3) the guna avatars
4) the manvantara avatars
5) the yuga avatars
6) the shaktyavesha avatars

1) Purusha avatars:

Krishna first incarnates as the three purusha avatars namely:

Karanodakashayi Vishnu – “The Lord who is lying on the causal ocean”.

Garbhodakashayi Vishnu – “The Lord who is lying on the universal ocean”

Kshirodakashayi Vishnu – “The Lord who is lying on the milk ocean”.

This is described in the Satvata tantra.

Karanodakashayi Vishnu, (Maha Vishnu) – the first purusha incarnation.

The expansions of Krishna who come to the material creation are called avatars or incarnations.

This means ‘one who descends from the spiritual realm’. From the innumerable planets in the spiritual sky, some expansions of the Lord descend into the universes.

The first descent of the Supreme Personality of Godhead from the expansion of Sankarshana (Balarama) is the first purusha incarnation, known as Maha Vishnu, or Karanodakashayi Vishnu. It is confirmed in the Srimad Bhagavata Purana (1.3.1):

jagrhe paurusam rupam
bhagavan mahad-adibhih
sambhutam sodasa-kalam
adau loka-sisrksaya

“In the beginning of the creation, the Lord first expanded Himself in the universal form of the purusha incarnation and manifested all the ingredients for the material creation. And thus at first there was the creation of the sixteen principles of material action. This was for the purpose of creating the material universe.”

Maha Vishnu lies within the Causal ocean – this ocean is the spiritual water that emanates from the gigantic body of Maha Vishnu, in which all the universes are floating.

Electrified by the power of Maha Vishnu the material nature at once creates innumerable universes in this ocean. Thus it is called as karana – Causal ocean.

He is the original incarnation within the material world. He is the Lord of time, nature, cause and effect, mind, ego, the five elements, the three modes of material nature , the five senses, and the universal form.

Although He is the master of all objects movable and immovable in the material world, He is totally independent.

The material creation is effected by the interaction of the three modes of material nature set in action by the Lord. He exists before the modes of material nature are set in motion.

The sruti mantra confirms this: that only Narayana (one who lies in the water emanating from His body – i.e., Maha Vishnu) existed before the creation:

eko vai narayana asin na brahma na isano napo nagni-samau neme dyav-aprithivi na naksatrani na suryah

“In the begining of the creation there was only the Supreme Personality Narayana. There was no brahma, no Siva, no fire, no moon, no stars in the sky, no sun.”

Srimad Bhagavatam (2.9.10) describes the Causal ocean:

pravartate yatra rajas tamas tayoh
sattvam ca misram na ca kala-vikramah
na yatra maya kim utapare harer
anuvrata yatra surasurachitah

“In that personal abode of the Lord, the material modes of ignorance and passion do not prevail, nor is there any of their influence in goodness. There is no predominance of the influence of time, so what to speak of the illusory, external energy; it cannot enter that region. Without discrimination, both the demigods and the demons worship the Lord as devotees.”

The first purusha avatar, Maha Vishnu glances over the material nature , and the material nature becomes agitated by this glance. Thus the Purusha avatar impregnates matter with living entities. This act of glancing is described in the Upanishads “sa iksate”

Simply by the glance of the first purusha incarnation, consciousness becomes present within the matter . This consciousness is known as mahat tattva. This created consciousness is then divided into three departmental activities according to the three gunas, goodness (sattva), passion (rajas), and ignorance(tamas), the modes of material nature.

The cosmic manifestation is a combination of all three modes and their products of creation and in this way innumerable universes are created.

By the breathing of Maha Vishnu all the universes are generated in seed form and gradually develop into gigantic forms with innumerable planets within each and every universe. The seeds of universe s develop into gigantic forms in the same way as seeds of a banyan tree develop into numberless banyan trees.

These universes are produced from the pores of the body of Maha Vishnu. As He breathes out, they come out and when he inhales they enter into Him again. So the duration of existence of each universe is only a breath time of the first purusha incarnation, Maha Vishnu.

In the Brahma samhita it is stated:

yasyaika-nisvasita-kalam athavalambya
jivanti loma-vilaja jagad-anda-nathah
visnur mahan sa iha yasya kala-viseso
govindam adi-purusham tam aham bhajami

“Brahma and other lords of the mundane worlds, appearing from the pores of hair of Maha-Vishnu, remain alive as long as the duration of one exhalation of the later [Maha-Vishnu]. I adore the primeval Lord Govinda of whose subjective personality Maha-Vishnu is the portion of portion.”

Thus Mahavisnu by breathing causes the seeds of universes to come out of the pores of His gigantic body, and by glancing impregnates the material nature with living entities.

All of the energies of Maha Vishnu are totally spiritual, and they have nothing to do with the material energy.

The process by which He interacts with the material energy for the purpose of creation, namely impregnating the material nature with the living beings and the universal seeds will be explained in the guna avatar section.

Garbhodakashayi Vishnu – the second purusha incarnation:

The second purusha incarnation enters into each and every universe. He spreads water from His body, and He lies down on His divine snake bed (this snake form is another expansion of the Lord, in the avesa category, known as Ananta-sesa).

From His naval , the stem of a lotus flower grows, and within the stem of that lotus flower are the fourteen divisions of planetary systems. The lotus flower on the top is the planet of Brahma, known as Satyaloka.

In the Srimad Bhagavatam (1.3.26) this is described:

yasyambhasi sayanasya
yoga-nidram vitanvatah
nabhi-hradambujad asid
brahma visva-srjam patih

“A part of the purusha lies down within the water of the universe, from the navel lake of His body sprouts a lotus stem, and from the lotus flower atop this stem, brahma, the master of all engineers in the universe, becomes manifest.”

Within each universe Garbhodakashayi Vishnu is present and He maintains each universe and tends to its needs. Although He is within the material universes, the influence of material energy cannot touch Him.

He is worshipped as the Hiranyagarbha (golden source) Supersoul, He is the master of the universe. The vedic hymns describe Him as one having thousands of heads. The universe is described as a form of this Vishnu – virat rupa (gigantic form).

Kshirodakashayi Vishnu – the third purusha incarnation.

The third incarnation of Vishnu, Kshirodakashayi Vishnu resides on the island known as Shveta-dvipa (white island) in the middle of the ocean of milk within the universe. He is the Supersoul of all living entities (seated in their heart) and all material objects (seated in every atom).

He is an expansion of Garbhodakashayi Vishnu and from Him all incarnations within the universe are expanded.

visnos tu trini rupani
purushakhyany atho viduh
ekam tu mahatah srastr
dvitiyam tv anda-samsthitam
trtiyam sarva-bhuta-stham
tani jnatva vimucyate

“For material creation, Lord Krishna’s plenary expansion assumes three Vishnus. The first one, Maha-Vishnu, creates the total material energy, known as the mahat-tattva. The second, Gabhodakashayi Vishnu, enters into all the universes to create diversities in each of them. The third, Kshirodakashayi Vishnu, is diffused as the all-pervading Supersoul in all the universes and is known as Paramatma. He is present even within the atoms. Anyone who knows these three Vishnus can be liberated from material entanglement.”

2) Lila avatars:

A list of lila avatars (pastime incarnations) is given in the Srimad Bhagavatam:
1) Kumaras
2) Narada
3) Varaha
4) Matsya
5) yajna
6) Nara-Narayana
7) Kardami
8) Dattatreya
9) Hayasirsa
10) Hamsa
11) Dhruvapriya or Prsniggarbha
12) Rsabha
13) Prthu
14) Nrsmha
15) Kurma
16) Dhanvantari
17) Mohini
18) Vamana
19) Bhargava Parasurama
20) Ramachandra
21) Vyasa
22) Prlambhari Balarama
23) Krishna
24) Buddha
25) Kalki
Out of these Hamsa and Mohini are momentary incarnations within the material world. They do not reside in the spiritual realm.

Kapila, Dattatreya, Rsabha and Dhanvantari are eternal forms from the spiritual realm and are more celebrated.

Kurma, matsya, Nara-narayana, Varaha, Hayasirsa, Prsnigarbha and Balarama are considered as vaibhava (expansions of emotion) incarnations.

Krishna is confirmed as the source of all these incarnations:

ete camsa-kalah pumsah
krishnas tu bhagavan svayam
indrari-vyakulam lokam
mrdayanti yuge yuge

“All of the above-mentioned incarnations are either plenary portions or portions of plenary portions of the Lord, but Lord Sri Krishna is the original Personality of Godhead. All of them appear on planets whenever there is a disturbance created by the atheists. The Lord incarnates to protect the theists.” – Srimad Bhagavatam 1.3.28

3) Guna avatars:

For the purpose of creation, maintenance and annihilation of the universe, the Lord incarnates qualitatively, as in-charge of the three material qualities, viz., goodness, passion and ignorance.

Goodness: The third purusha incarnation, Kshirodakashayi Vishnu acts as the incarnation in the mode of Goodness also, even though He is always situated above the modes. He is the master of the mode of goodness in each universe. But in no way in touch with the influence of the modes.

Passion: Garbhodakashayi Vishnu directly empowers a very qualified living entity (jiva) as the primal living entity of the universe, to be the chief engineer of the creation. He is known as Brahma. He is manifested from Garbhobakashayi Vishnu on the lotus that emanates from Vishnu’s naval. In the Brahma samhita Brahma is likened to valuable jewels influenced by the rays of the sun, and Garbhodaka Vishnu is that sun.

If there is no suitable living entity capable of serving as Brahma, Garbhodakashayi Vishnu Himself expands as Brahma for creation within the universe.

Ignorance: By expanding as Lord Siva, the Lord becomes the annihilator of the universe when needed. Lord Shiva in association with Maya, (the external material energy of the Lord) has many forms , which are categorically numbered at eleven, known as rudras (angry person)

Lord Shiva is not one of the living entities (like Brahma). He is more or less, Krishna Himself. The example of milk and yogurt is given in this regard. Yogurt is a preparation out of milk , but still in that form it cannot be used for the purpose of milk.

Similarly in the Rudra aspects of Lord Shiva , who is a guna avatar of Krishna, one cannot seek spiritual restoration as one can from Krishna. The essential difference is that Lord Shiva as in-charge of the department of annihilation is in connection with the material nature, whereas Vishnu or Krishna has nothing to do with the material nature.

siva sakti-yuta sasvat
tri-lingo guna-samvrtah
vaikarikas taijasas ca
tamasas cety aham tridha

“Lord Shiva is always united with his personal energy, the material nature. Manifesting Himself in three features in response to the entreaties of nature’s three modes, he thus embodies the threefold principle of material ego in goodness, passion and ignorance.”

4) Manvantara avatars:

Brahma’s day – 1,000 catur yugas – is divided into fourteen periods of the rule of Manus (fathers of mankind) known as manvantaras. The incarnations during these manvantaras are listed as follows:
1) Yajna
2) Vibhu
3) Satyasena
4) Hari
5) Vaikuntha
6) Ajita
7) Vamana
8) Sarvabhauma
9) Rsabha
10) Visvaksena
11) Dharma
12) Sudhama
13) Yogesvara
14) Brhadbhanu
Yajna and Vamana are also lila avatars. All the fourteen of them are vaibhava category.

Manus, the fathers of mankind and the rulers of the manvantaras, are also incarnations of Krishna in the category of manvantara avatars. There are fourteen manus in a day of Brahma. In the life time of Brahma there are 504,000 Manus. Each Manu of the fourteen are described by a different name:
1) Svayambhuva Manu, son of Brahma;
2) Svarocisa Manu, the son of Agni, the fire god;
3) Uttama Manu, the son of King Priyavrata;
4) Tamasa Manu, the brother of Uttama Manu;
5) Raivata Manu, the brother of Tamasa;
6) Caksusa Manu, the brother or Tamasa, but son of Caksu;
7) Vaivasvata Manu, the son of Vivasvan, the sun god (the present Manu);
8) Savarni Manu, also a son of sun god, born of wife Chaya;
9) Daksasavarni Manu, the son of Varuna;
10) Brahmasavarni Manu, the son of Upasloka;
11) Rudrasavarni 12) Dharmasavarni 13) Devasavarni and 14) Indrasavarni Manus are all sons of Upasloka.

5) The Yuga Avatars:
There are four yugas which come in cycles:

Satya yuga, lasting 1,728,000 years
Treta yuga, lasting 1,296,000 years
Dwapara yuga, lasting 864,000 years
Kali yuga, lasting 432,000 years
In each of these yugas the Lord incarnates with a different body colour according to the yuga.

asan varnas trayo hy asya
grhnato ‘nuyugam tanuh
suklo raktas tatha pita
idanim krishnatam gatah

“Krishna appears as an incarnation in every millennium. In the past, He assumed three different colors – white, red and yellow – and now he has appeared in a blackish color.” – Srimad Bhagavatam 10.8.13

In the Satya yuga a white avatar appeared to Kardama muni to establish meditation as the process for self-realization.

In the Treta yuga a red avatar appeared to Brahma to establish fire sacrifice as the process for self-realization.

In the Dvapara yuga a dark avatar (Krishna) appeared as the son of Devaki to establish temple worship as the process for self-realization.

In the Kali yuga a Yellow avatar appeared (Chaitanya Mahaprabhu) as the son of Sachi Mata to establish the chanting of the holy names (nama-sankirtana) as the process for self-realization.

6. Shaktyavesha avatars – Empowered Incarnations

There is no limit to the number of shaktyavesha incarnations. But some are mentioned in the vedic literatures as examples. They are of two kinds, direct and indirect.

When the Lord Himself expands displaying a particular power of His opulences He is known as Sakshat.

When He empowers a living entity with some particular sakti – power, for some specific activity, to represent Him , that living entity is called indirect or avesha incarnation.

Avesha incarnations:

Four Kumaras empowered with knowledge.
Narada empowered with devotional service.
Brahma empowered with creative power.
King Pritu empowered with power to maintain living beings.
Parasurama empowered with power to kill evil elements.

Sakshat incarnations:

Sesa (snake with Garbhodakasayi Vishnu) empowered with power to sustain the planets.
Ananta (snake with Ksirodakashayi Vishnu and other expansions) empowered to serve the Lord.

Sometimes a single incarnation will simultaneously be more than one category. To cite examples, Lord Sri Ramachandra is both within the lila avatar and the yuga avatar categories. Similarly Lord Varaha is also simultaneously within the lila avatar and the yuga avatar categories.

Apart from the specific six categories of avatars, there is also a distinct category known as Vibhuti – special favor from the Lord. Any living entity who is exceptionally strong, beautiful, knowledgeable, wealthy, famous and renounced should be known to be specially favored by the Lord.

There are two features to be studied in understanding the incarnations of the Lord.

The principal feature called personality and the marginal feature called function or activity. In the Vedic scriptures there are descriptions of the characteristics of the body of an incarnation, and this is the principal feature by which an incarnation is identified.

The activities of the incarnation are the marginal features.

All the incarnations are mentioned in the scriptures. The features of the incarnation and the particular type of mission which He has to execute are mentioned .The great sages, by the symptoms mentioned, declare an incarnation.

The innumerable incarnations of the Lord are manifested all over the universes constantly, without cessation, as water flows constantly from waterfalls. Their presence is just like the sun in the sky, even if it is not seen from one place, it is always there, and thus the scriptures describe the pastimes of the incarnations as eternal.

Prahlad Maharaj, in his prayer to the incarnation Lord Narasimha says, “You manifest as many incarnations as there are species of life, namely aquatics, plants, reptiles, birds, beasts, men, and the demigods, just for the maintenance of the faithful and the annihilation of the unfaithful .You advent yourself in this way in accordance with the necessity of the different yugas. In the Kali yuga you incarnate garbed as a devotee”

(This devotee incarnation is Lord Chaitanya, who is explicitly mentioned in many scriptures.)

idam bhagavatam nama
puranam brahma-sammitam
uttama-sloka-caritam
cakara bhagavan rsih
nihsreyasaya lokasya
dhanyam svasty-ayanam mahat

“This Srimad Bhagavatam is the literary incarnation of God, and it is compiled by Srila Vyasadeva, the incarnation of God. It is meant for the ultimate good of all people, and it is all-successful, all blissful and all-perfect.” – Srimad Bhagavatam 1.3.40

In the Srimad Bhagavatam there are selected histories of great devotees who are in direct contact with the Supreme Personality of Godhead. There are descriptions of various incarnations of the Lord. One can derive the ultimate blessings of the Lord and His devotees by careful and patient study of this literature. Thus this sound form of Sri Krishna is also considered as an incarnation and worshiped as respectfully as one will worship the Lord and His incarnations.

It is defined as brahma sammitam because it is the sound representative of Brahman. It is the sound representative of the Lord. Bhagavad gita which is spoken by the Lord (whose sound is non different from Him) and the Srimad Bhagavatam spoken by the empowered incarnation of the Lord, Vyasa, about the activities of the Lord and His devotees (these descriptions are also non different from Him) are both incarnations of the Lord , in the form of transcendental sound vibrations revealing timeless wisdom to the conditioned souls.

One can desire from the study of the Bhagavatam all benefits that are possible to be derived from the personal presence of the Lord and His incarnations.

nigama-kalpa taror galitam phalam
suka-mukhad amrta-drava samyutam
pibata bhagavatam rasam alayam
muhur aho rasikabhuvi bhavukah

“O expert and thoughtful men, relish Srimad Bhagavatam, the mature fruit of the desire tree of Vedic literatures. It emanated from the lips of Sri Sukadeva Gosvami. Therefore this fruit has become even more tasteful, although its nectarean juice was already relishable for all, including liberated souls.”

As the Lord is all light, all bliss and all perfection, so also is Srimad Bhagavatam . One can have all the transcendental light of the Supreme Lord Sri Krishna and His incarnations from the recitation of this sound incarnation of the Lord provided it is done perfectly.

There are two forms of the Srimad Bhagavatam: one is the book and the other is a person, known as bhagavata, the transparent teacher of Srimad Bhagavatam who is a pure devotee of the Lord, in the highest platform of self realization.

Only from the person bhagavata, one can understand the lessons of book Bhagavatam perfectly.

The person bhagavata leads his life in terms of the book Bhagavatam. The Bhagavatam book and the person bhagavata are thus identical. The messenger and the messages of the Lord are non different from Him. Whenever the messenger of the Supreme Personality of Godhead undertakes offenseless glorification and hearing of the Lord , He is present there in the form of transcendental sound , which has the same power as the Lord.

The Lord is so kind to the living beings that He is present before them in the form of transcendental sound vibration. Apart from the messages of the literary incarnation, Srimad Bhagavatam, He is present in His holy names. These holy names have all the potencies of the Lord endowed by Him. Therefore the innumerable names of the Lord are also incarnations in sound form.

The taste for hearing and chanting the holy sound incarnations of the Lord is developed through the medium of service to the pure transparent bhagavata devotee of the Lord as described in the Srimad Bhagavatam (1.2.18):

nasta-prayusv abhadresu
nityam bhagavata-sevaya
bhagavaty uttam-sloke
bhaktir bhavati naisthiki

“By regular attendance in classes on the Bhagavatam and by rendering service to the pure devotee, all that is troublesome to the heart is almost completely destroyed, and loving service unto the Personality of Godhead, who is praised with transcendental songs, is established as an irrevocable fact.”

Common reasoning may fail to understand this process of serving the person bhagavata and the book Bhagavatam for the purpose of gradual promotion on the path of devotion which bestows the association with the Lord Himself. But great sages like Narada , who are the authorities on the subject confirm that the more progress is made in devotional service under the guidance of the person bhagavata , the more one becomes fixed in the transcendental loving service of the Lord Himself.

In the modern age (five centuries ago) Lord Chaitanya Mahaprabhu preached the sound incarnation Srimad Bhagavatam by practical demonstration as a person bhagavata. By His causeless mercy it has become easier to penetrate into the topics of the Srimad Bhagavatam.

Lord Sri Chaitanya Mahaprabhu is the selfsame Lord Sri Krishna. In this incarnation, however, He appeared as a great devotee bhagavata of the Lord, in order to preach to the people in general, as well as religionists and philosophers, about the transcendental position of Sri Krishna the primeval Lord and the cause of all causes, based on the book Bhagavatam.

The essence of His teachings is that:

1) Lord Sri Krishna, who appeared in Vrajabhumi (Vrindavana) as the son of the King of Vraja (Nanda Maharaja) is the Supreme Personality of Godhead, and therefore worshipable by all.

2) Vrindava dhama is nondifferent from the Lord, because the name, form, and place where the Lord manifests Himself are all identical with the Lord as absolute knowledge. Therefore Vrindavana dhama is as worshipable as the Lord.

3) The highest form of transcendental worship of the Lord was exhibited by the gopis (cowherd girls) of Vrajabhumi in the form of pure affection for the Lord, and this process is the most excellent mode of worship.

4) Srimad Bhagavatam, the sound form of the Lord, is the spotless purana (book of history) for understanding the Lord.

5) The ultimate goal of life for all living beings is to attain the stage of prema (love of God).

Sri Chaitanya Mahaprabhu is the yuga avatar of the age of Kali. He is both Bhagavan and Bhagavatam in person and in sound.

Therefore His process of approaching the Srimad Bhagavatam is practical for all people of the world. It was His wish that people worldwide should be given an opportunity to hear the sound incarnations of the Lord, viz., the holy names of Krishna and the Srimad Bhagavatam.