Dasharatha performs Ashvamedha Yagam
Dasharatha decided to perform the Vedic ritual, 'Ashvamedha Yagam'. Following this, Dasharatha also wanted to perform "Putra Kameshti" ritual to beget children. King Dasharatha requested sage Rushyasrung to conduct the Vedic ritual on his behalf as he wished to beget offspring for preserving his family lineage. Rushyasrung replied that the paraphernalia for ritual could be gathered and the ritual horse could be released as a right. Brahman scholars and sage Vasishta applauded king Dasharatha for keeping Rushyasrung at the helm of affairs. They also blessed him that his intention to beget sons through Vedic ritual will be fulfilled and he will get four sons with great qualities.
Vasishta commencing works related to the ritual
On completion of one full year and on arrival of another spring season King Dasharatha came to Vasishta and informed him that the horse returned successfully. The performer of such rituals is expected to perform ae preliminary ritual for a period of one year, which was completed. Dasharatha requested Vasishta that the ritual be performed systematically and conducted in such a way that no obstacle of whatsoever, occurred. Vasishta assured all his support and confirmed that whatever that is requested or decided by the king would be materialised.
Vasishta nominates Sumantra for inviting kings
Vasishta told Sumantra about the activities that he needs to attend on his own for the ritual. Vasishta told that all those kings on the earth were to be invited. He also told to extend invitation to Brahmins, Kshatriyas, Vaisyas and Sudras in large numbers. On hearing Vasishta, Sumantra immediately ordered sincere emissaries to invite all the kings to their kingdom. Kings from different parts of the earth arrived at Ayodhya, responding to the invitation from Dasharatha. They came with rich gifts in tune with their ability and on knowing this Dasharatha felt very happy.
Ashvamedha Yagam commences
Then after completion of one year and on retrieval of the ritual horse, Dasharatha commenced the Vedic ritual of 'Ashvamedha Yagam' on the northern banks of River Sarayu. Knowledgeable performers of Vedic rituals called Ritwiks started works related to the yagam as per standards and conducted them traditionally and customarily. Brahmans have traditionally performed all of those other rituals connected to the main one methodically. All these were performed under the leadership of Rushyasrung and joined by other Ritwiks. King Dasharatha smelt the smell of smoke as per time and procedure to cleanse his own sin. On completing the ritual Dasharatha justifiably donated those lands to the Ritwiks.
Dasharatha commences Putra Kameshti
Rushyasrung agreed to the request of King Dasharatha to conduct the Putra Kameshti ritual that bestows sons. Then Rushyasrung commenced the Putra Kameshti offering necessary oblations into sacred fire. When this was done, the heavenly divinities along with celestial beings like Gandharvas, Siddhas, Devatas, esteemed sages etc. came along with Lord Brahma and assembled there to receive their part of oblations from the ritual of Dasharatha.
Gods and Goddesses pleading Brahma to save them from Ravana
The heavenly divinities, the Gods and Goddesses who assembled there in the congregation pleaded to Brahma like this: "Oh! Lord Brahma! With your benedictions and blessings, the monster king Ravana is torturing all of us ostensibly with the courage he got that none can do anything to him. We are incapable to control him. You gave him a boon that he has no death in the hands of heavenly bodies like Devatas and with due respect to your boons we are tolerating all his acts and not killing him. He is torturing not only us, the celestial beings, but also all the three worlds. His desire is to dethrone Lord Indra from heaven. Under the guise of your boons he is indiscriminately harassing the Yakshas, Gandharvas, Asuras, Brahmins and so on".
In reply to them Brahma said, Ravana got boon and approval from him that he shall not be killed by Yakshas, Gandharvas, Asuras, Gods or by other demons but did not care about humans and monkeys out of disrespect to them. And that is why he shall be killed by human only. All the Devatas and Gods and Goddesses were pleased with the assurance of Brahma.
Arrival of Lord Vishnu in front of Devatas
Meanwhile, Lord Vishnu arrived there on his Eagle chariot Garatmanth, in front of Devatas obviously to assure them that he will take care of them. On his arrival and on his standing by the side of Lord Brahma, all the Gods and Goddesses offered prayers to him. Later they briefed Vishnu about their panic.
They told Lord Vishnu about their plight like this. "Oh! Vishnu, the Leader of entire universe! Please take birth as human being through the wives of King Dasharatha and eliminate Ravana in war failing which he will eliminate all of us. Ravana has been torturing all of us along with sages and saints, Gandharvas, Siddhas etc. He knocks down the chariots of Gandharvas and Asuras as well as other Gods while they were on their journey from place to place. We are all here to request you to annihilate enemies of divinity like Ravana, the monster king, and hence you make-up your mind to born as a human being".
Vishnu's assurance to Devatas
When Lord Vishnu was eulogized this way by the Gods and Devatas, he told them to get rid of their fear first. Vishnu assured that he will kill the cruel and evil-minded demon king Ravana along with all his near and dear. Subsequently, Vishnu started giving a thought to his birth as human being and also about the person who deserves to have him as his son. Vishnu finally decides to be born to King Dasharatha and manifests himself in four forms. Having understood the thought process of Lord Vishnu, all the celestial bodies including Lord Shiva and Brahma praised Vishnu and offered prayers with a request to eliminate Ravana.
Devatas praying Lord Vishnu to incarnate as human
Vishnu elicited his view to Devatas as to how he should incarnate himself and how he should adopt the strategy so that he will be able to kill Ravana. They all suggest to him that it should be in form of human being and he should assume the same. They told him, "Ravana performed severe penance, for several years with which Lord Brahma was pleased and gave a boon to him that he shall not face fear of death from anyone except human beings, since Ravana did not care them; dubbing them as inferiors. Having got this unequivocal boon from Brahma, Ravana became extremely arrogant and started torturing the three worlds, which included abducting women. Hence his annihilation lies in the hands of humans alone." On hearing this from Gods, Lord Vishnu decided to choose Dasharatha as his father in the human world.