Divine power depends strongly on faith and belief. The stronger a believer's faith is, the more divine power they can draw from their god. But unlike what people think, that feeling of faith must be mutual. It isn't hard for a mortal to have faith in a god, but for a god to have faith in a mortal, that's near impossible.
The deeper and stronger a paladin's faith becomes, the more their god starts to believe in them, and the more faith he'll have in them to finish their duties. The more they'll become that god's champion.
The stronger that mutual feeling of faith grows, the stronger the link between the god and their champion would be, allowing more power to be circulated.
Arad knows Kali's power well. He had seen her rinse the world once before. To him, she is the true definition of a god, of a divine being with so much incomprehensible and unfathomable power to deserve being called a true goddess. What is the being that could command destruction itself if not a god?
