Srimad-Bhagavatam: Canto 12 - Chapter 1 - Verse 24
Sanskrit:
कलौ तु धर्मपादानां तुर्यांशोऽधर्महेतुभि: ।एधमानै: क्षीयमाणो ह्यन्ते सोऽपि विनङ्क्ष्यति ॥ २४ ॥
ITRANS:
kalau tu dharma-pādānāṁturyāṁśo ’dharma-hetubhiḥedhamānaiḥ kṣīyamāṇohy ante so ’pi vinaṅkṣyati
Translation:
In the Age of Kali only one fourth of the religious principles remains. That last remnant will continuously be decreased by the ever-increasing principles of irreligion and will finally be destroyed.