The legend is that at a very remote period when the gods felt their powers weakened and were desirous of obtaining amrita the beverage of immortality, Vishnu directed them to churn, together with the demons, the ocean of milk. For this purpose they took the mountain Mandara as the churning stick. But they could succeed only when Vishnu himself consented to support the mountain on his back; after having assumed the shape of a gigantic tortoise.
From the churning of the ocean, in addition to the ambrosia of immortality, the following substances came forth:
1). Dhanvantri, the physician of the gods,
2). Lakshmi, the goddess of fortune,
3). Varuni, the wine goddess,
4). Soma, the sacrificial elixir,
5). Apsaras, the celestial nymphs,
6). Uccaihshravas, the divine horse,
7). Kaustubha, the celestial jewel,
8). Parijata, the celestial tree,
9). Surabhi, the wish cow,
10). Airavata, the royal elephant,
11). Panchajanya, the conch,
12). Sharanga, the bow, and
13). Halahala, the poison.
Here the four-armed Kurma Avatara is shown carrying the symbolic attributes of Vishnu.
The upper-right arm holds the mace. The mace of Vishnu is known as Kaumodaki, which literally means "that which inebriates the mind." The mace thus represents the power of knowledge, because knowledge dazzles and intoxicates the mind. Also all physical and mental powers are derived from the power of knowledge. Nothing else can conquer time and itself become the power of time. As such the mace is identified with the goddess Kali, who is the power of time. According to the Krishna Upanishad "The mace is Kali, the power of time. It destroys all that opposes it."
The second right arm holds the lotus. The lotus represents detachment, for though this beautiful flower grows in muddy waters, neither water nor dirt are ever seen sticking to its petals. Like the lotus, Vishnu is the partaker of life's pleasures who never gets ensnared by the charms of the world.
The upper-left hand holds the discus. The discus of Vishnu is known as Sudarshana, which literally means beauteous-sight. It symbolizes a sharp instrument which severs obstacles in the attainment of enlightenment.
The other left hand holds the conch. The conch is the symbol of the origin of existence. It has the form of a multiple spiral evolving from one point into ever-increasing spheres. It is thus associated with the elemental waters. When blown, it produces a sound associated with the primeval sound from which creation developed.
Below the central figure can be seen the yantra of the Kurma Avatara.
This description by Nitin Kumar, Executive Editor, Exotic India.
Danielou, Alain. The Myths and Gods of India: Vermont, Inner Traditions International, 1991.
Garrett, John. A Classical Dictionary of India: Delhi, Low Price Publications, 1996.
Pattanaik, Devdutt. Vishnu - An Introduction: Mumbai, Vakils, Feffer and Simons Ltd., 1999.
Santiago, J.R. Sacred Symbols of Hinduism: Delhi, Book Faith India, 1999.