Antoni Vila Delclòs, plastic artist and stained glass historian, gave an interesting lecture on the history of stained glass and its role as an artistic and spiritual element. Vila reviewed the double function of stained glass since its inception in Europe in the 11th-12th centuries. On one hand, the physical closure to protect people and temper the inclemency of weather inside the churches; on the other, to explain stories and, therefore, moralize society. These two functions have always been linked to each other and have been complemented, and they have grown technically and aesthetically until today, although this art has often been considered as minor and linked to architecture. It is not until the early twentieth century that these concepts change and are transformed, evolving and giving the art of stained glass an even broader concept with the incorporation of abstraction as a form of expression. Vila also explained his work in the Sagrada Família, in collaboration with his father, the artist Joan Vila Grau.