Shloka 1.6.5
अयोध्यावर्णनम् — Description of Ayodhya under Daśaratha
तेन सत्याभिसन्धेन त्रिवर्गमनुतिष्ठता ।पालिता सा पुरी श्रेष्ठा इन्द्रेणेवामरावती ।।1.6.5।।
tena satyābhisandhena trivargam anutiṣṭhatā |
pālitā sā purī śreṣṭhā indreṇevāmarāvatī ||1.6.5||
By that king—steadfast in truth and rightly pursuing the three aims of life—this finest city was governed and protected, like Amarāvatī by Indra.
King Dasaratha, who always kept his word and followed dharma, attained prosperity and pleasure in equal measure by righteous means ruled that best of the cities as Indra ruled Amaravati.
Satya as a foundation of rule: a king who is true to his word and aligns artha and kāma under dharma creates an orderly, flourishing society.
Ayodhyā is being portrayed as an ideal city because its ruler upholds truth and balanced life-goals.
Truthfulness/faithfulness to promises (satyābhisandha) together with disciplined pursuit of life’s aims.