Rameshwari gathered the great seers, kings, scholars, townsfolk, experts in ancient lore, grammarians, and the aged, brahmans, on behest of Shri Ram.

She then fetched Luv Kush, and told them the Kaushalya-nandan has invited them to sing the song of his life in the interval of the yagya.

"Dekho, tum dono ghabrana mat. Maharaj Ram Chandra atyant dayalu hai. Humare Pita hai woh." Rameshwari said.

"Humare ?" Luv asked and Rameshwari pressed her lips, sadly.

"Ha Luv, Maharaj toh praja ke Pita hote hai. Gurudev ne bhi yahi kaha tha." Kush said.

"Satyavachan." Luv nodded.

"Chale ?" Rameshwari asked in a gentle tone.

"Ha !" They both said excitedly, beaming with delight.

And so she brought them in the gathering and then went to her seat. All the people there stared at Luv Kush, as if drinking in their images with their eyes. The assemblage then broke down into whispers.

"Yeh dono toh hu-bahu Shri Ram ki chhavi hai."

"Aisa lag raha ki Ram ka darpan mei pratibimb ho."

"Yadi inhone valkal aur jata dharan nahi ki hoti, toh hum Raghav aur inme antar bhi nahi bata paate."

Shri Ram who was keenly looking at them both, knew instantly that they were his sons born from his wife, his beloved Sita.

the twins began a song that enhanced the delight of those who heard it. Then that sweet and ethereal musical performance took place there, and because of the perfection of the singing, none of those who heard it could get enough of it.

First, it commenced from the beginning, that is, from the sarga in which there was the meeting with Narad Muni. Continuing from there, they sang twenty sargas.

It became afternoon, when Luv Kush has finished singing 20 sargas.

"Bharat, inn dono balako ko abhi issi kshan, 18000 swarn mudraye do." Shri Ram said.

But the two great bards were perplexed and would not accept the gold that was being offered.

"Hum toh Vanachari hai. Vano mei nivaas karte hai. Hum swarn ka kya karenge ?" Luv asked.

"Maharaj, hum toh keval kandmool aur falo mei santusht rehte hai. Hume swarn ki koi awashyakta nahi." Kush said.

As the two of them were speaking in this fashion, Ram and all those who were listening were greatly amazed and were filled with curiosity.

"Uchit hai." Shri Ram smiled.

Together with the sages, kings, and Vanars, Shri Ram listened to the supremely wonderful singing for many days.

And when the Luv Kush had sung the 500 Sargas of Ramayan, in its entirety, Shri Ram said the following words in the midst of the assembly.

"Brahmarishi Valmiki ke upasthiti mei jaa kar kehna, 'Yadi Sita kalankheen hai ya usne apne paap ka prayaschit kar liya hai, toh aapki aagya se, Kal pratah Sita yaha aake apne pavitrata ki shapat le. Iss kalank ko mitaane hetu, Janak-Suta Maithli, yaha aaye.' Yeh apne Guru se kehna." Shri Ram said in a gentle and sweet tone.

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A/N

So the myth that Shri Ram didn't know about whom the Ramayan was about comes from this part from Sarga 85 of Uttar Kaand -

But in the very same Sarga 85, in the beginning, there is this line -

So Shri Ram knew it was about him, but maybe he asked it so everyone in the assembly knows.

And mind it, this is after they sing the first 20 sargas only. Entire Ramayan is sung after this.