1) ADI PURUSH AVATAR (Incarnation as the Pre-eminent man) :
Lord Vishnu took his first incarnation as the pre-eminent man, with a desire to commence creation. This first incarnation of Lord Vishnu was full of all the sixteen Kalas (Supernatural powers).
Lord Brahma manifested from the navel of Lord Vishnu in his (Lord Vishnu) state of Yoganidra (deep meditation). The creation as well as the expansion of the creation commenced from the organs of Lord Brahma. The first incarnation of Lord Vishnu is all-powerful, which can be seen only by the yogins and sages who have attained divine knowledge. This incarnation is also the indestructible seed from which all the other incarnations manifest themselves. During the time of final annihilation of the world, every creation merges into him.
2) THE ETERNAL YOUTHS :
Sanatkumar was the ‘Manasputra’ (born by a wish) of Lord Brahma. Throughout his life, he maintained celibacy; and engaged himself in the performance of tremendous penance. He was the one from whom the Brahmins got the inspiration regarding the values and importance of penance and Celibacy.
3) VARAHA AVATAR (The incarnation as a Boar) :
Lord Vishnu took his third incarnation as a boar. In this incarnation Lord Vishnu rescued the earth which had submerged in the ocean, and brought it out from the ocean. The whole creation started only after that. A demon by the name of Hiranyaksha had abducted the earth and carried it to the ‘Rasatala’ (the second lowest of the world). The earth is considered to be as a ‘Woman’ and since it is a crime to abduct a woman therefore Lord Vishnu in his incarnation of a boar killed the demon Hiranyaksha and liberated the earth from his clutches.
4) NARADA AVATAR (The incarnation as Sage Narada) :
Lord Vishnu took his fourth incarnation as Narada. Narada by becoming a ‘Devarishi’ among all the sages, achieved liberation from all of his Karma’s (action). Narada was the one who gave discourses to the Vaishnavas (followers of Lord Vishnu) on ‘Pancharatra Tantra’.
Lord Vishnu in his incarnation as Narada, showed that, the devotion is the best mean of getting liberated from all the bondages of ‘Karma’s’. He also said that a devotee of Lord Vishnu is the supreme among the devotees in the same way as Devarishi Narada among the Sages.