Valmiki Ramayana Ayodhya Kanda Sarga 61 Shloka 22
Original Shlokaनैवं विधमसत्कारं राघवो मर्षयिष्यति। बलवानिव शार्दूलो वालधेरभिमर्शनम्।।2.61.22।।
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बलवान् strong, शार्दूलः tiger, वालधेः of its tail, अभिमर्शनम् इव like twisting, राघवः Rama, एवं विधम् such, असत्कारम् insult, न मर्षयिष्यति will not tolerate.
A powerful tiger will not allow its tail to be twisted. In the same way Rama also will not tolerate an insult of this sort.