In Catholicism, magic is rejected and seen as something from the devil, witches, heathens and probably heresy. Miracles (which could be seen as magic by others) dont use a spell or a ritual as fair as I know.
According to this
Conspirancies & Catholicism - Magic
All practices of magic or sorcery, by which one attempts to tame occult powers, so as to place them at one’s service and have a supernatural power over others – even if this were for the sake of restoring their health – are gravely contrary to the virtue of religion. These practices are even more to be condemned when accompanied by the intention of harming someone, or when they have recourse to the intervention of demons
In a Certain Magical Index, Catholics are seen portraying all kinds of magical powers. Now I don't know much about the non-catholic cristian anglican puritan english church , but I doubt they allow magical rituals in their practices either.
Why nuns, bishops and catholics have magic powers in A Certain Magical Index? Is it just because of ignorance of the japanese authors about the Catholic (and perhaps also English puritan church) religions , or is there any reason which gives an argument to this inside the story?