Srimad Bhagavatam Canto 12, Chapter 04, Text 36

SB 12.4.36

kala-sroto-javenasu
 hriyamanasya nityada
parinaminam avasthas ta
 janma-pralaya-hetavah
 
Translation: 
 
All material entities undergo transformation and are constantly and swiftly eroded by the mighty currents of time. The various stages of existence that material things exhibit are the perpetual causes of their generation and annihilation.
Srimad Bhagavatam Canto 12, Chapter 04, Text 35
Srimad Bhagavatam Canto 12, Chapter 04, Text 37