The reading of the texts of Saint Teresa of Jesus and the spiritual impact that Enric D´Ossó, founder of the congregation, had on Gaudí, powerfully influenced the conceptual layout of the interiors and exteriors of the College project. Samples of them are the crenellations and the pinnacles, which give an appearance of fortification to the building and which refer to the book Castillo Interior (1577), one of the main Teresian works, where the writer compares the human soul to a fortress.