Deities and Divine Intervention
Seldomly will the divine entities in this world directly intervene in worldly affairs. They are caught in a delicate balance of power between each other and rather let the mortals carry out their will.
The main goal of a deity is to gain more followers, inspire blind faith in them and cement its own power among the various forces of the realm beyond the veil. The favorites of a god are rewarded with powerful answers to their prayers.
Even for the divines, piercing through the veil is difficult and strenuous and manifesting an avatar or incarnation even more so. This only happens when the stakes are exceedingly high.
It becomes much easier at places or times where the worlds intersect and the veil gets thinner. These places are often home to churches, temples, shrines and other sacred places where pilgrims gather.
Pious religious leaders and devoted missionaries often unknowingly gather a considerable amount of divine favor which shields them from harm. When they pray to their god, an answer is almost sure to follow.
A deity might occasionally communicate with its followers through dreams and visions or in extremely rare cases through an incarnation.