tad-ańga-prabhavaḿ śańkham
ādāya ratham āgamat
tataḥ saḿyamanīḿ nāma
yamasya dayitāḿ purīm
gatvā janārdanaḥ śańkhaḿ
pradadhmau sa-halāyudhaḥ
śańkha-nirhrādam ākarṇya
prajā-saḿyamano yamaḥ
tayoḥ saparyāḿ mahatīḿ
cakre bhakty-upabṛḿhitām
uvācāvanataḥ kṛṣṇaḿ
sarva-bhūtāśayālayam
līlā-manuṣyayor viṣṇo
yuvayoḥ karavāma kim
tat -- his (the demon's); anga -- from the body; prabhavam -- grown; sankham -- the conchshell; adaya -- taking; ratham -- to the chariot; agamat -- He returned; tatah -- then; samyamanim nama -- known as Samyamani; yamasya -- of Lord Yamaraja; dayitam -- beloved; purim -- to the city; gatva -- going; jana-ardanah -- Lord Krishna, the abode of all persons; sankham -- the conchshell; pradadhmau -- blew loudly; sa -- accompanied by; hala-ayudhah -- Lord Balarama, whose weapon is a plow; sankha -- of the conchshell; nirhradam -- the resounding; akarnya -- hearing; praja -- of those who take birth; samyamanah -- the restrainer; yamah -- Yamaraja; tayoh -- of Them; saparyam -- worship; mahatim -- elaborate; cakre -- performed; bhakti -- with devotion; upabrimhitam -- overflowing; uvaca -- he said; avanatah -- bowing down humbly; krishnam -- to Lord Krishna; sarva -- of all; bhuta -- living beings; asaya -- the minds; alayam -- whose residence; lila -- as Your pastime; manushyayoh -- appearing as human beings; vishno -- O Supreme Lord Vishnu; yuvayoh -- for the two of You; karavama -- I should do; kim -- what.
The conchshell the Lord took from Pancajana, which is called Pancajanya, is the same one He sounded at the beginning of the Bhagavad-gita. According to the acaryas, Pancajana had become a demon in a way similar to that of Jaya and Vijaya. In other words, though appearing in the form of a demon, he was actually a devotee of the Lord. The Skanda Purana, Avanti-khanda, describes the wonderful things that happened when Lord Krishna sounded His conchshell:
asipatra-vanam nama
sirna-patram ajayata
rauravam nama narakam
arauravam abhut tada
abhairavam bhairavakhyam
kumbhi-pakam apacakam
"The hell known as Asipatra-vana lost the sharp, swordlike leaves on its trees, and the hell named Raurava became free of its ruru beasts. The Bhairava hell lost its fearfulness, and all cooking stopped in the Kumbhipaka hell."
The Skanda Purana further states,
papa-kshayat tatah sarve
vimukta naraka narah
padam avyayam asadya
"Their sinful reactions eradicated, all the inhabitants of hell attained liberation and approached the spiritual world."