Simple: The Church does not reprimand priests for preaching where they please (a de-facto reality anyway, since priests can't be excommunicated) while at the same time only declaring a crusade when a priest is actually tortured or executed (something that has already been proposed by King Turin).
Of course individual realms such as Kabrinskia may declare wars if they wish, but one theocracy does not make a crusade and King Turin seems to believe that a mere arrest is not a cause for Iashalur to declare war.
I think most would agree to that though what if a priest repeatedly gets arrested and the realm decides to deport the priest as a way for the priest to stop preaching there. (I understand the church says there is nothing wrong with preaching in other realms but what would the church's reaction be if a priest got deported for this?)
