Are discussed in this article the relationship between Lorca's religious buildings and the earthquake that affected the city last May 11th, from two sides: First, considering seism itself as a chaotic fact, although with a series of rules that apply to all buildings equally. Second, the buildings response to the stresses caused by the movement of the earth. A final section discusses the actions taken by the technicians responsible for the work in the churches, the procedures followed in drafting reports, the relationship with the relevant entities and the actual performance of emergency work.