The Kurma avatar appears in Ancient Vedic texts, and he is a popular avatar among the vaishnavites.
Once, sage Durvasa cursed the Devas (demi gods) to lose their powers because they did not respect him. In order to regain their power, the demi gods decided to churn the cosmic ocean of milk to get the divine drink (AMIRTHA). For churning the ocean of milk, they have used Mount Mandara, Serpent Vasuki and Lord Kurma.
The Demons took the divine drink, and Lord Vishnu manifested himself as the beautiful Mohini and mesmerized the Demons, and then he distributed the divine drink to the Devas. The Devas after drinking the divine drink, had regained their powers, and defeated the demons easily.
Kurma Temple in Chittoor District of Andhra Pradesh
Kurmanathar Temple in Chitradurga District of Karnataka
Kurma Swamy Temple in Hooghly district of West Bengal
Lord Vishnu has taken this avatar mainly to give the divine power to devas by generating divine drink (AMIRTHA) from the ocean. Through this avatar, he has protected devas. Hence he was praised and worshipped by the demi gods.
Lord Kurma is a great avatar of Lord Vishnu, who takes this avatar for restoring devas to their original power, and also to defeat the demons. Let us pray to Lord Kurma and be blessed.