Om is the underlying and the first sound of the manifested creation. It is the basis of everything. But it originates from a layer so subtle that the normal human mind cannot comprehend its force. It is often heard in deep states of dhyan, as many Sanatan Kriya practitioners at Dhyan Ashram have reported.
This sound, however, can be heard easily when one puts a shankh (conch) to the ear. The shankh is believed to be one of the first sound producing agencies, through which the sound of Om emanates. Blowing of the shankh also produces the sound of Om. It is called Shankhnad. It is this amazing property of shankh which endows it powers of creation and healing, as has been put to use since time immemorial.
This instrument is considered a gift of the ocean and was one of the 14 ratnas produced during the Samudra Manthan – the legendary churning of the ocean.
A symbol of Lord Vishnu, the shankh, when blown, dispels negative energy. It also declares the victory of good over evil and hence was used as a war trumpet in earlier times.
Lord Krishna is believed to have blown the Panchjanya Shankh before the commencement of the Mahabharata War, declaring in the beginning itself that the opponents would lose.
A book titled Tantropathy, by RP Upadhyay, has listed experiments done by a group of German scientists on the sound of the shankh. During the course of the experiment, they found that diseases like cholera, plague and thyroid cannot survive in an environment where the shankh is blown regularly. Moreover, the sound actually helps in alleviating these diseases.
The specific geometry of a shankh is considered to generate remarkable energy-effects. More extraordinary is the fact that these are formed naturally. Different kinds of shankhs are therefore used as yantras for different purposes in the mantra and tantra based sadhnas.
The Daksinvarta shankh, which has spirals turning in the counter-clockwise direction, is considered to be the most valuable and is believed to be the abode of Goddess Laxmi – the consort of Lord Vishnu. This variety is only found in the Indian Ocean and that too very rarely.
The Brahma Vaivarta Purana declares that bathing in the waters led through a Daksinvarta shankh is considered to be the equivalent to bathing with all holy waters at once.
Shankhs also hold great importance in Ayurveda. Drinking water stored in certain types of conches is believed to cure various types of diseases as the water absorbs the medicinal and healing properties of the conch.
Conch shell ash or shankh bhasm is also used as a medicinal remedy.