On this page
In the mansion of Prajapati Daksha, the drums of celebration sounded that day. One after another, beginning with Ashwini, he had placed the hands of all twenty-seven of his daughters into the keeping of Chandra, the moon. Having won Chandra as their lord, the maidens shone like the constellations strung across the night sky, and Chandra, blessed with such wives, grew more radiant by the hour. To anyone who watched, it looked as though twenty-seven stars had gathered into a garland around a single hero, and the whole of the night had been drawn into one soft light.

But among these twenty-seven was one named Rohini. No other wife was ever as dear to Chandra as she was. His entire mind, all his time, and his whole gaze inclined toward Rohini alone. This caused the remaining daughters deep sorrow. When sisters share a single lord and his affection narrows to only one of them, that same ache rose in their hearts. They rose together and sought refuge with their father, and told Daksha everything that was happening.
Hearing his daughters’ sorrow, Prajapati Daksha too grew downcast. He came to Chandra and spoke in a very calm voice. Kalanidhi, keeper of the moon’s digits, he said, you were born into a pure and noble line. Toward all the women who live under your shelter, why does your heart hold this measuring out of more and less? To give one greater affection and another less does not become you. With the same feeling with which you took one to yourself, take them all. What has happened until now has happened. Never again behave with such partiality, for such conduct is said to lead a man all the way to hell.

Having made this appeal, Daksha returned home fully convinced that the imbalance would now be erased. But destiny was the stronger force. Bound by a powerful fate, Chandra sank even deeper into Rohini, and the honor due to his other wives went as neglected as before. When this news reached him, Daksha grew sorrowful once more. He came again in person, and speaking of sound conduct and of justice, he began to plead with Chandra for equal treatment.
Daksha’s curse
Daksha said, Chandra, listen. Many times before this we have made you the same appeal, and still you have not heeded our words. Therefore today we lay this curse upon you, that the wasting disease should take hold of you.
The moment he spoke, the wasting disease seized Chandra. His digits began to shrink day by day, and the light of the night grew dim and pale. As the moon dwindled, a great cry of distress rose across the whole world. The gods and the sages, stricken with worry, began to say, what will happen now, how will Chandra ever be whole and well again? Sunk in this sorrow, everyone was overcome. Chandra himself described his plight to Indra and the other gods and to the sages. When no path forward could be found, Indra and the gods together with Vasishtha and the other sages went to take refuge with Brahma.

Brahma’s remedy
Having heard them all, Brahma said, gods, what has already come to pass cannot be turned back; the curse cannot be erased. But its effect can be relieved. I will tell you an excellent remedy; listen to it with respect. Let Chandra go with the gods to the sacred region called Prabhasa. There, performing the rite of the Mrityunjaya mantra in the prescribed manner, let him worship Lord Shiva. Let him install a Shivalinga before himself and keep to tapas, austerity, without a day’s break. Pleased by this, Lord Shankara will free him of the wasting disease.

Worship at Prabhasa
At the urging of the gods and the sages, and obeying Brahma’s command, Chandra went to the region of Prabhasa. There he installed a Shivalinga before himself and kept to tapas without pause for six months. With the Mrityunjaya mantra he worshipped Lord Mrityunjaya, the conqueror of death, made a hundred million repetitions of the mantra, and stood unbroken with a steady mind, meditating on Mrityunjaya throughout. Seeing his devotee absorbed in such austerity, Lord Shankara, tender toward those who love him, was pleased, and appearing before him, he spoke.

Shankara said, Chandra, may all be well with you. Ask for whatever your heart desires as your boon. I am pleased, and I will grant you every excellent gift.
Chandra said, lord of the gods, when you are pleased, what could remain impossible for me? Even so, my lord, drive this wasting disease from my body, and forgive whatever offense I may have committed.
Shiva said, Chandra, in one fortnight let a single digit of yours wane each day, and in the other fortnight let that same digit go on growing without pause. This is why the moon is seen now to shrink and now to swell.
After this, Chandra praised Lord Shankara with heartfelt devotion. Shiva, who had been without form, took form again for the sake of his devotee. Pleased with the gods, and to raise the glory of that region and to spread Chandra’s fame through all three worlds, Lord Shankara came to be called Someshwara there, after Chandra’s own name Soma, and grew renowned across the three worlds as Somnath. Among the Jyotirlingas, his is the very first name to be spoken.
The glory of Somnath
When a worshipper honors Somnath, Lord Shankara destroys his consumption, his leprosy, and his other diseases. Blessed is that Chandra, and fulfilled in every purpose, by whose name the lord of all three worlds, Lord Shankara himself, sanctifies the earth and abides forever in the region of Prabhasa.
There too all the gods established the Somakunda, the pool in which Shiva and Brahma are held to dwell forever. This Chandrakunda is famed upon the earth as a tirtha, a pilgrimage water that destroys sin. Whoever bathes in it is freed from all sins. Incurable diseases such as consumption are undone by bathing in that pool for six months. Whatever desire a person carries when resorting to this excellent tirtha, that desire he surely obtains, of this there is no doubt.
By the power of this boon and this tirtha, Chandra was cured, and he returned to his work as before. This is the katha of the manifestation of Somnath, the first of the Jyotirlingas. Whoever listens to it with devotion, or recites it to others, is forever released from all sins.

Source: Shiva Purana (Gita Press, Sankshipt Shivpurank), Kotirudra Samhita