Originally Posted by FreeTheSlaves
Most characters should be polytheistic and invoke various gods depending on what they're doing or where they're going, and not have one particular deity.

Having a singular deity is the unusual exception.
It's the exception that explains where Divine spellcasting comes from. It's borrowed power granted through devotion. I think Paladins as a spellcaster class should be very clear on this even though otherwise they could be polytheistic. Otherwise the lines between Arcane and Divine magic blur away and the gods' role comes under question, if they are not actually needed for Divine magic. "Faithless" people getting access to the same powers would shake the foundations of many faiths.