The Ramayana gives an exalted place to satya or truth. The exile of Rama was a turning point in the story of the Ramayana and that took place only to keep the word of King Dasaratha’s old promise true. Dasaratha died but did not renounce the truth. He had made a verbal promise to Kaikeyi, and Rama accepted exile in the forest for fourteen years to protect the promise of his father.
In its eulogy of truth, the Ramayana state that rajya (the state) is truth-based and the world also rests upon satya (truth). Rishis and gods recognized satya only. A truthful person of this world achieves an abode that cannot be destroyed. People become unhappy and scared when they see a liar as if they have seen a serpent.
Dharma based on satya is called the root of all, and there is no place higher than that of satya.
Satya is God, and dharma always depends on satya.
Dana (charity), alms, oblation, penance and Vedas are founded on satya. Therefore, one should be truthful. (Valmiki Ramayana 2/109/10-14)