In the chapters 14-19 of Parvati Khanda in Shiva Purana, the story of Kashyap, Diti and their grandson Tareka is mentioned.
Diti and Aditi, both were daughters of Daksh Prajapati one of the Manas Putra (born of the mind) of Lord Brahma. Both of them were married to Rishi Kashyapa who was one of the Saptarishis. With Diti, Kashyap fathered all the Daityas / asuras while with Aditi he fathered all the devas, the eldest one being the sun who consequently came to be known as Aditya (son of Aditi).
Brahma’s son Marichi begot Kashyap who married thirteen daughters of Dakṣha. The eldest of them Diti bore two sons: Hiranyakashipu the elder and Hiraṇyakṣa the younger. When these two began to harass the gods, Vishnu assumed the forms of Man-lion and Boar and killed them. Then the gods became fearless and happy.
The distressed Diti sought refuge in Kashyap and observing the sacred rites she conceived. On coming to know of it, Indra entered her womb forcibly and cut it off many a time with his thunderbolt. By the power of her sacred rites, the child in the womb did not die as she was sleeping at that time, by a stroke of good luck. They were cut into seven pieces and so she had seven sons. These sons became gods by the name of Maruts. They all went to heaven along with Indra and were taken as his own attendants by the king of gods.
Diti repented to her husband for her action. She made the sage pleased by means of great service. Kashyap said: --
“Be pure and perform penance for ten thousand years of Brahma. When it is completed, you will have a son.”
Birth & Marriage of Vajranga, the son of DIti:
The penance was completed by Diti and from him she conceived and delivered of a son. That son of Diti named Vajranga (of adamantine limbs) was on a par with the gods. Befitting his name, his body was strong and powerful even from his very birth. At the bidding of his mother, he immediately abducted Indra, the lord of gods, the other gods and punished them in various ways. Seeing the distress of Indra and others, Diti became very happy. Indra and other gods became miserable due to their own actions.
Brahma got released the gods. Vajranga, a great devotee of Shiva, was delighted in his heart, and he of pure soul, without any aberration, spoke. Vajranga said: --
“To achieve his interest, Indra killed the foetus of my mother. He has now tasted the fruit thereof. Well may he rule over his kingdom. O Brahma, I did this only at the bidding of my mother. I have no desire for the enjoyments of any one of the worlds. Tell me the essence of real philosophy whereby I can ever remain happy, pleased in heart and free from aberrations.”
On hearing that, Brahma said: --
“Sattvic feelings constitute the essence of real philosophy. I shall lovingly create an exquisite lady.”
Brahma ji offered him a lady named Varangi. With chastity and faith, she served her husband lovingly in diverse ways. Her husband Vajranga of great lordly status was glad very soon on account of her service. He then spoke thus: --
“O beloved, what do you wish? What is it that you cherish in your mind? On hearing that, she bowed to her husband and revealed her desire.”
Varangi said: --
“O my good husband, if you are so pleased grant me a powerful son who will conquer three worlds and cause misery to Vishnu.”
On hearing the words of his beloved, he was disagreeably surprised and vexed. He was free from inimical thoughts. With perfect wisdom and Sattvic feelings in his heart he said: --
“My beloved wishes enmity with the gods. It does not appeal to me. What shall I do? Where shall I go? How can my vow be preserved from destruction? If my wife’s wishes are fulfilled, the three worlds will be much distressed, so too the gods and the sages. If my beloved’s desires are not fulfilled, I am sure to be cast into hell. In either case righteousness will be lost. This is what we have heard. After weighing both the alternatives, he agreed to the proposal of his wife. For that purpose, he performed another very difficult penance with great zeal with Brahma as the object of worship, for number of years. On seeing the great penance Brahma went to him for granting the boon. With a delighted mind Brahma told him “Speak out the boon you wish to have.”
He eulogised Brahma as well as craved for the boon as desired by his wife.
On hearing his words, Brahma said “So be it.”
Birth of Tareka, the grandson of DIti and his boons:
Then Varangi conceived and delivered of a son of huge body and great strength dazzling the ten quarters. At the same time, the phenomena of three varieties indicating great calamity and terrifying the worlds occurred in the sky, heaven, and earth. Then Kashyap Prajapati thought well and named the powerful demon Taraka. That heroic demon, with his manliness and valour manifesting quickly grew and developed with his steely frame like the lord of mountains. Then the demon Taraka, of great strength and exploit, endowed with a lofty mind, requested permission of his mother for performing penance. The permission having been secured, that demon performed a severe penance.
Brahma told him thus— “tell me what boon you want. A severe penance has been performed by you. There is nothing which cannot be granted to you”.
Taraka said: --
“O Pitamaha, if you are glad and ready to grant me two boons, there should certainly be no man equal to me in strength in this entire universe created by you. If a son born of Shiva becomes the commander-in-chief of an army and discharges weapons against me, let my death occur then”.
Brahma granted him two boons and hastened back to my abode. That great demon was crowned the king of the three worlds with the permission of Shukra, the preceptor of the demons. Then the great demon became the leader of the three worlds. He inaugurated his commanding position by harassing the mobile and immobile beings.
Afraid of him, Indra surrendered his Airavata (white elephant) and Kubera all his nine treasures. White horses were surrendered by Varuṇa, the wish-yielding cow Kamdhenu by the sages, and the sun out of fear for him surrendered his divine horse, Uchchaihsravas. The three worlds became void of all valuable things. The oceans the offered him their gems on account of fear. The entire earth became exuberant in productivity without being tilled and yielded what his subjects desired. Whatever riches the gods possessed, or the manes or others had, were forfeited by the wicked demon. Bringing the three worlds under his control, he declared Indra himself. He became the undisputed lord and ruled over them with perfect self-control. Dismissing the gods, he installed demons in their places. Some gods he engaged in his personal service.
The gods terribly tormented by Taraka, bowed to and eulogised Brahma, the lord of subjects with great devotion. On hearing the eulogy of the gods pleasing and true to facts Brahma was highly pleased and asked: “Why have you all come here? Tell me.”
The gods said: --
“The demon Taraka is very haughty. Driving us out with force he has taken possession of our positions. Please dispel our misery quickly. Wherever we flee we see Taraka. Agni, Yama, Varuṇa, Nirṛti, Vayu and other guardians of the deities are under his control. All of us are his servants. The charitable and virtuous activities are being seldom pursued in the worlds. The regions of our three worlds have been forcibly taken, Taraka have sinful and ruthless temperament. You are our final resort. We had some hope of victory in Sudarshan the discus of Vishnu. But even that discus has become ineffective in his neck where it has fallen as though it were a floral offering to a deity.
Brahma said: --
“O gods, the demon Taraka has flourished, due to my words of blessings. His destruction through me does not seem proper. Shiva is the most suitable agent to carry out your task. Thanks to the power of the boon granted by me, Taraka cannot be killed by me or by Vishnu or by Shiva or by any one of the gods. It is true. O gods, if there is a son born of Shiva, he alone can kill the demon, Taraka. O gods, it is certain that lord Shiva will marry her. Still, you shall pursue your endeavour.
The third eye of Shiva and death of Kamadeva:
Kama and his wife Rati have been powerful enough to conquer the three worlds through sentiments of love esp. in Vasanth. Indra remembered Kama for help.
Kama was deluded by Shiva’s illusion. Accompanied by his wife and Spring he went to the place where Shiva, the Yogi, was performing penance. After going there, the haughty Kama, deluded by Shiva’s magic power, first spread the enchanting power of Spring all around. The fragrant flowers of Mango and Asoka trees shone heightening feelings of love. The water lilies with bees hovering on them proved to be the causes for the rise of love in the minds of everyone. The sweet cooings of the cuckoos heightened emotions of love. The bright light of the moon scattered all around appeared to be the emissary of lovers and their beloveds. Thus, the vast diffusion of Spring caused the display of emotions of love. It was unbearable to the forest dwelling sages.
On seeing the untimely display of spring, Shiva the lord, who had assumed a physical body indulging in divine sports, thought it surprising. But He continued his severe penance. Enchanting all people, he spread his influence.
Kama could not find any vulnerable loophole in Shiva whereby he could enter Him. In the meantime, Parvati came there along with her two maids and brought various kinds of flowers for Shiva’s worship. Profiting by that opportune moment, Kama, by means of his arrow Harṣaṇa delighted the moon-crest god Shiva who was nearby. In order to make the trident-bearing lord take interest in her, Kama drew his bow very carefully and discharged his flowery arrow on Him. As was her usual practice she approached Shiva, bowed to Him, worshipped Him, and stood in front of Him (awaiting further instructions). Parvati was stared at by lord Shiva, while she was laying bare some of the limbs bashfully, as is natural to women in such circumstances.
On seeing Parvati, Shiva said:
“I feel great pleasure on merely seeing her. What pleasure shall I derive by embracing her?”
Thinking thus only for a moment, the enlightened Shiva became detached, honoured Parvati, and spoke.
“How wonderful and mysterious is the situation that has arisen! How is it that I have been deluded and fascinated? Though I am the lord and master, I have been perturbed by Kama.”
Shiva said: --
“How is it that obstacles have cropped up while I am performing the great penance? Who can be that wicked person who has made my mind highly perturbed? With love I have described in bad taste another man’s woman. I have contravened rules of virtue and transgressed the bounds of the Vedas.”
After thinking like this, the great Yogi, the goal of the good, surveyed all round, his suspicion having been aroused. He saw Kama stationed on His left side with his bow fully drawn and ready to discharge the arrow. Kama was haughty and so was very senseless. On seeing Kama in that attitude, instantaneously anger was aroused in lord Shiva, the supreme soul. Kama discharged his arrow, usually unerring on Shiva. The infallible weapon became futile on the great lord. When his endeavour became futile, Kama who was frightened much remembered Indra and all other gods. Third eye Shiva killed Kama.
There are two forces – positive and negative. Positive force is represented by Aditi who gave birth to Devas and Negative force is represented by Diti who gave birth to Datiyas. Positive forces preserve the world and negative forces destroys it.