Valmiki Ramayana Ayodhya Kanda Sarga 79 Shloka 7
Original Shlokaज्येष्ठस्य राजता नित्यमुचिता हि कुलस्य नः। नैवं भवन्तो मां वक्तुमर्हन्ति कुशला जनाः।।2.79.7।।
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नित्यम् always, नः our, कुलस्य race, ज्येष्ठस्य the eldest one, राजता kingship, उचिता हि is befitting (tradition) indeed, कुशलाः intelligent, जनाः people, भवन्तः all of you, माम् me, एवम् in this way, वक्तुम् to tell, न अर्हन्ति does not behove.
It has been the tradition in our race that the eldest son alone should always inherit the kingdom. It does not behove intelligent people like you to tell me like this.