Valmiki Ramayana Aranya Kanda Sarga 5 Shloka 18
Original Shlokaएतद्दि किल देवानां वयो भवति नित्यदा। यथेमे पुरुषव्याघ्रा दृश्यन्ते प्रियदर्शनाः।।3.5.18।।
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प्रियदर्शनाः men of delightful counterance, इमे these, पुरुषव्याघ्राः best of men, यथा as, दृश्यन्ते they are seen, एतत् this way perhaps, देवानाम् for gods, वयः age, नित्यदा always, constant भवति किल remains verily.
These tigers among men have cheerful countenacess from which it can be deduced that the age of the gods always remains constant.