Śrīmad-Bhāgavatam · Text 11.1.17
Who is speaking and story frame
तच्छ्रुत्वा तेऽतिसन्त्रस्ता विमुच्य सहसोदरम् ।
साम्बस्य ददृशुस्तस्मिन् मुषलं खल्वयस्मयम् ॥ १७ ॥
tac chrutvā te ’ti-santrastā
vimucya sahasodaram
sāmbasya dadṛśus tasmin
muṣalaṁ khalv ayasmayam
Upon hearing the curse of the sages, the terrified boys quickly uncovered the belly of Sāmba, and indeed they observed that therein was an iron club.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.