currently, sworn enemy/rival is not affecting (at the very least) priest spells and abilities when a templar targets a foe who has been marked.  holy radiance and divine mark, for example, when utilized by a templar against a marked foe do not benefit from damage or accuracy bonuses.

 

nothing in the description of sworn enemy/rival suggests the benefits is limited to weapon accuracy and damage.  am assuming the paladin multiclass should benefit from spell accuracy and damage... or maybe not. is possible this ain't a bug but is only an ambiguity.  

 

as an aside, another quirky priest bug is resulting from the lash damage of spiritual weapons, such as the flail o' eothas, being applied to spell damage.  a templar with a spiritual flail equipped will add corrode damage when utilizing the aforementioned divine mark.

 

HA! Good Fun!

Sworn Enemy also does not affect Mind Blades for accuracy or damage.

As far as I know it doesn't even work with ranged weapons, only melee ones.

Just because someone's your Sworn Rival doesn't mean you're going to pull out all the stops to defeat them 

This will be resolved in the next Beta update. In the current build, Marked Prey and Sworn Enemy weren't granting their bonuses for ANY ranged attack - weapon, spell, etc. These abilities have been refactored for the next update.