Valmiki Ramayana Ayodhya Kanda Sarga 109 Shloka 14
Original Shlokaदत्तमिष्टं हुतं चैव तप्तानि च तपांसि च। वेदा स्सत्यप्रतिष्ठाना स्तस्मात्सत्यपरो भवेत्।।2.109.14।।
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दत्तम् charity, इष्टं च sacrifice, हुतं चैव libation, तप्तानि mortifications, तपांसि च asceticism, वेदाः the Vedas, सत्यप्रतिष्ठानाः have truth as the foundation, तस्मात् therefore, सत्यपरः भवेत् one should adhere to truth.
Charity, sacrifice, libations, mortifications, asceticism and the Vedas have truth as their foundation. Therefore, every one should be an adherent of truth.