It was stated by Mareecha, while advising Ravana to desist from the idea of abducting Sita.
रामो विग्रहवान् धर्मः साधुः सत्य पराक्रमः |
राजा सर्वस्य लोकस्य देवानाम् इव वासवः || ३-३७-१३"Rama is the embodiment of righteousness, he is an equable person with truthfulness as his valour, and as with Indra to all gods he is the king of entire world. “
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A) Generally, people quote the first line only - रामो विग्रहवान् धर्मः - Shri Rama is embodiment of DHARMA, in order to eulogise Shri Rama’s virtues.
If we carefully study the 2nd part of the shloka, we can find that Sage Valmiki quoted 3 more qualities of Shri Rama, for which also the phrase embodiment of - विग्रहवान् -applies.
रामो विग्रहवान् - Shri Rama is embodiment of
धर्मः - Dharma
साधुः - Goodness (not to harm anyone, unprovoked)
सत्यः - TRUTH
पराक्रमः - Valour
So, Shri Rama is embodiment of Dharma, Goodness (not to harm anyone, unprovoked), TRUTH and Valour.
B) राजा सर्वस्य लोकस्य देवानाम् इव वासवः
Shri Rama is the king of entire world as Indra, with all the above qualities, to all gods.
Here, Sage Valmiki was saying that Indra too have all the above qualities and thus Indra is the embodiment of Dharma, Satya, Goodness and Valour among Gods.
Generally, rishis say embodiment of TRUTH will make a person the God, as the formless God/BRAHMAN is embodiment of TRUTH - सत्यः.
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In Rig Veda, the formless BRAHMAN was eulogised in different epithets like AGNI, INDRA, VISHNU, RUDRA, etc.
स स्तोम्यः स हव्यः सत्यः सत्वा तुविकूर्मिः । एकश्चित्सन्नभिभूतिः ॥
sa stomyaḥ sa havyaḥ satyaḥ satvā tuvikūrmiḥ | ekaś cit sann abhibhūtiḥ ||
“He is to be praised, he is to be invoked, he is embodiment of TRUTH, powerful the doer of many deeds; he, being single,is the overcomer (of his foes).”
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Hence, Sage Valmiki, while stating that Shri Rama was the embodiment of Satya (TRUTH), was hinting subtly the Shri Valmiki was the BRAHMAN itself.
