Valmiki Ramayana Bala Kanda Sarga 58 Shloka 3
Original Shlokaइक्ष्वाकूणां हि सर्वेषां पुरोधा: परमो गुरु:। न चातिक्रमितुं शक्यं वचनं सत्यवादिन:।।1.58.3।।
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सर्वेषाम् for all, इक्ष्वाकूणाम् kings of Ikshwaku race, पुरोधा: their spiritual preceptor, परम: is highly, गुरु: venerable one, सत्यवादिन: truthspeaking one, वचनम् word, अतिक्रमितुम् to by pass, न शक्यम् not capable of being done.
For all the kings of the Ikshvakus race, their chief priest is their Guru. It is not possible to bypass the spiritual preceptor who is true to his word preceptor.