Srimad Bhagavatam Canto 12, Chapter 10, Text 41

SB 12.10.41

etat kecid avidvamso
 maya-samsrtir atmanah
anady-avartitam nrnam
 kadacitkam pracaksate
 
Translation: 
 
Although this event was unique and unprecedented, some unintelligent persons compare it to the cycle of illusory material existence the Supreme Lord has created for the conditioned souls — an endless cycle that has been continuing since time immemorial.
 
Purport: 
 
Markandeya’s being drawn into the Lord’s body by His inhalation and expelled again by His exhalation should not be considered a symbolic description of the perennial cycles of material creation and annihilation. This portion of the Srimad-Bhagavatam describes a real, historical event experienced by a great devotee of the Lord, and those trying to relegate this story to mere symbolic allegory are here declared to be unintelligent fools.
Srimad Bhagavatam Canto 12, Chapter 10, Text 40
Srimad Bhagavatam Canto 12, Chapter 10, Text 42