Lord Vishnu descends on earth whenever there is a decline in religious practice and a predominant rise of irreligion. In the Vedas, it is said that the Lord, although one without second, manifests himself in innumerable forms. Each and every incarnation has a particular mission, and all these forms and their missions are described in the revealed scriptures. The essence of each mission is to restore people's obedience to religious principles, leading them to God consciousness.

Sometimes Vishnu descends personally, sometimes he sends his bonafide representative in the form of his son or servant, and sometimes he comes himself in a disguised form. The ten major incarnations of Vishnu are collectively known as the Dasavatara.

The Dasavatara incarnations also represent ten different conditions that living beings may generally experience, from the beginning of their bondage up to the end:

Invertebrate - Matsya
Testaceous, shelly - Kurma
Vertebrate - Varaha
Crectly vertebrate, half man, half beast - Narasimha
Manikin - Vamana
Barbaric - Parasurama
Civilized - Ramacandra
Wise - Krsna
Ultra-wise - Buddha
Destructive - Kalki