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Adityahridayam
Ādityahṛdayam (, ), is a devotional hymn associated with Aditya or the mobile Sun God (Surya) and was recited by the sage Agastya to Rāma on the battlefield before fighting the demon king Rāvana. This historic hymn starts at the beginning of the duel between Rāma and Rāvana. Agastya teaches Rāma, who is fatigued after the long battle with various warriors of Lanka, the procedure of worshiping the Sun God for strength to defeat the enemy. These verses belong to Yuddha Kānda (Book 6) Canto 107, in the Rāmāyana as composed by Agastya and compiled by Vālmīki.