Valmiki Ramayana Sundara Kanda Sarga 50 Shloka 2
Original Shlokaकिमेष भगवान्नन्दी भवेत्साक्षादिहागतः।।5.50.2।। येन शप्तोऽस्मि कैलासे मया सञ्चालिते पुरा। सोऽयं वानरमूर्तिस्स्यात्किंस्विद्बाणो महाऽसुरः।।5.50.3।।
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एषः he who, पुरा earlier, मया by me, कैलासे when Kailasa, सञ्चालिते when shaken, येन by that, शप्तः अस्मि I was, भगवान् lord, साक्षात् personally, इह here, आगतः has come, नन्दी Nandi, किं भवेत् could he be?, सः अयम् ths same, वानरमूर्तिः in vanara form, महासुरः great demon, बाणः Bana, स्यात् किं स्वित् could be himself.
'Is he Lord Nandi who came here in person? I was earlier cursed by him when I shook the mount Kailasa in the past. Could he have assumed a monkeyform or may be he is the great demon Bana. (Nandi is the bull, the vehicle of Lord Siva).