Valmiki Ramayana Kishkindha Kanda Sarga 1 Shloka 127
Original Shlokaतं मत्तमातङ्गविलासगामी गच्छन्तमव्यग्रमना महात्मा। स लक्ष्मणो राघवमप्रमत्तो ररक्ष धर्मेण बलेन चैव।।4.1.127।।
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मत्तमातङ्गविलासगामी who walks like a mighty intoxicated elephant, महात्मा great soul, सः लक्ष्मणः that Lakshmana, गच्छन्तम् as he went, राघवम् Rama, अप्रमत्तो vigilant, अव्यग्रमनाः with steady mind धर्मेण dutifully, बलेन चैव by his strength, ररक्ष protected.
The great soul, Lakshmana, striding like a mighty elephant, with a steady mind, followed Rama dutifully, protecting him with his strength.