Valmiki Ramayana Sundara Kanda Sarga 58 Shloka 154
Original Shlokaततोऽहं सुमहद्रूपं संक्षिप्य पुनरात्मनः।।5.58.153।। विमोचयित्वा तं बन्धं प्रकृतिस्थः स्थितः पुनः। आयसं परिघं गृह्य तानि रक्षांस्यसूदयम्।।5.58.154।।
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ततः then, अहम् I, आत्मनः my own, सुमहत् very huge, रूपम् form, पुनः again, संक्षिप्य assumed small form, तं बन्धम् that bondage, विमोचयित्वा got rid off, पुनः again, प्रकृतिस्थः into my natural huge form, स्थितः stayed, आयसम् near by, परिघम् iron beam, गृह्य took up, तानि रक्षांसि that rakshasas, असूदयम् killed.
"I reduced my form and rid of the bondage. Then again I assumed my original huge form and took up an iron bar lying near and killed all the demons (present).