Śrīmad-Bhāgavatam · Text 4.11.19
Who is speaking and story frame
सोऽनन्तोऽन्तकर: कालोऽनादिरादिकृदव्यय: ।
जनं जनेन जनयन्मारयन्मृत्युनान्तकम् ॥ १९ ॥
so ’nanto ’nta-karaḥ kālo
’nādir ādi-kṛd avyayaḥ
janaṁ janena janayan
mārayan mṛtyunāntakam
My dear Dhruva, the Supreme Personality of Godhead is ever existing, but in the form of time He is the killer of everything. He has no beginning, although He is the beginning of everything, nor is He ever exhaustible, although everything is exhausted in due course of time. The living entities are created through the agency of the father and killed through the agency of death, but He is perpetually free of birth and death.
Read Śrīla Prabhupāda's purport on Vedabase.io