In Hindu Mythology, Om (ॐ) is the essence of the supreme Absolute, consciousness, Atman, Brahman, or the cosmic world. Om is the prime symbol of Hinduism. In India there is a temple where the lord shiva manifested as Omkareshwar Jyotirlinga and Amaleshwar Jyotirlinga. It is on an island called Mandhata, at Khandwa district in Madhya Pradesh. The shape of the island is said to be like the Devanagari ॐ symbol.
Origin of Omkareshwar and Amaleshwar Jyotirlinga

There are three famous legends that are associated with the origin of this Jyotirlingas.
As per Hindu legend, Vindhya, the deity controlling the Vindhyachal mountain range was worshiping Shiva to propitiate himself from the sins committed. He created a sacred geometrical diagram and a Lingam made of sand and clay. Shiva was pleased with the worship and believed to have appeared in two forms, namely Omkareshwar and Amaleswara. Since the mud mound appeared in the form of Om, the island came to be known as Omkareswar. There is a shrine for Parvati and Ganapati in the temple.
The second story relates to Mandhata and his son’s penance. King Mandhata of Ikshvaku clan who was the ancestor of Lord Ram worshiped Lord Shiva here until the Lord manifested himself as a Jyotirlinga.
Some scholars also narrate the story about Mandhata’s sons-Ambarish and Muchukunda, who had practiced severe penance and austerities here and pleased Lord Shiva. Because of this, the mountain is named Mandhata.
The third story from Hindu scriptures says that once upon a time there was a great war between Devas (gods) and Danavas (demons), in which Danavas won. This was a major setback for Devas and hence Devas prayed to Lord Shiva. Pleased with their prayer, Lord Shiva emerged in the form of Omkareshwar Jyotirlinga and defeated Danavas.
About the Omkareshwar Jyotirlinga

Omkareshwar is the fourth in the twelve Jyotirlinga of Lord Shiva. The Omkar form Jyotirlinga is Shri Omkareshwar, that is, here Lord Shiva has appeared in the form of Omkar. Jyotirlinga is said to be the place where Lord Shiva himself appeared and is established in the form of light. All sins are consumed by the sight of Pranav Omkareshwar Jyotirlinga.
In the Puranas, the glory of Omkareshwar region is mentioned in Skanda Purana, Shiv Purana and Vayu Purana. There are a total 68 pilgrimages in Omkareshwar. Here 33 koti deities are seated. There are 108 impressive Shivling here in divine form. Shri Omkareshwar Jyotirlinga is the grand form of Narmada, which extends 84 yojanas, and is at a distance of 77 km from Indore, the main city of Madhya Pradesh. And this is the only Jyotirlinga which is situated on the north bank of Narmada. Lord Shiva comes here every day after touring all the three worlds and rests. Therefore, every day special sleeping arrangements and aarti of Lord Shiva are done here and there are sleeping darshans.
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