The sin of King Dasaratha

Sumantra takes leave from Sri Rama, and drives back to Ayodhya. Entering the royal gynaeceum, he submits to the emperor what transpired during journey. Dasaratha and Kausalya fall into a faint to hear about Sri Rama’s departure for Chitrakuta. 

 Kausalya, while weeping, rebukes Dasaratha for his evil act of sending Sri Rama to exile.  Afterwards, Kausalya repents for her mistake of speaking such crude words and consoles the king with her reconciliatory words.

 Recalling his earlier sin, he starts recounting the story of a young ascetic to Kausalya. He says that while he was Prince Regent of Ayodhya (60,000 years ago), he went out for hunting in a forest one day and heard the sound of a hermit-boy Sravana filling his pitcher with water by submerging it into Sarayu River. 

Mistaking the gurgling sound for trumpeting of an elephant Dasaratha hit the boy with an arrow, which went deep into the body and mortally wounded him.

 On approaching the victim, he discovered the fatal blunder and tendered his heart felt apologies to the hermit boy, who asked him to extract the arrow from his body and inform his parents. 

Dasaratha felt remorse for killing a brahmana boy.  Understanding his predicament, even at the verge of his death, Sravana informs him that he is not a brahmana boy.

संस्तभ्य धैर्येण स्थिरचित्तो भवाम्यहम् |
ब्रह्महत्याकृतम् पापम् हृदयादपनीयताम् ||  

'Suppressing my grief with firmness, I am becoming stable-minded. Let the torment in your heart, caused by the thought of your having killed Brahmana be removed.'

न द्विजातिर् अहम् राजन् मा भूत् ते मनसो व्यथा |
शूद्रायाम् अस्मि वैश्येन जातः जन पद अधिप ||  (Ayodhya Kanda 63 Sarga 52 - 53 Slokas)

'O, king the ruler of the country! I am not a Brahmana. Let there be no agony in your mind. I am born through a Sudra woman by a Vysya."

Sravana was the only son of his parents, who are blind and aged.  They are practicing religious austerities in the forest.

The boy died soon after the arrow was drawn out from the body.   King Dasaratha went to the aged parents of the deceased Sravana and informed about the death of their son and its cause and he escorted them to their son to the river, where he was lying dead. 

After embracing the boy they wept and offered libations of water to his spirit.  Finally the aged couple gave up their lives having cursed the king that he too would die of agony caused by the separation from his son.   Having thus narrated the story of his getting the curse long back and loudly weeping, king Dasaratha dies of grief.

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It can inferred from the above narration that in the Ramayana's period, inter-caste marriages were not prohibited.   Further, practising austerities by Vysyas and Sudras were not prohibited.