You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Pope_Paul_VI

Context:
He reminded the council fathers that only a few years earlier Pope Pius XII had issued the encyclical Mystici corporis about the mystical body of Christ. He asked them not to repeat or create new dogmatic definitions but to explain in simple words how the Church sees itself. He thanked the representatives of other Christian communities for their attendance and asked for their forgiveness if the Catholic Church is guilty for the separation. He also reminded the Council Fathers that many bishops from the east could not attend because the governments in the East did not permit their journeys.

Question:
What edict did Pope Pius XXIII issue regarding the body of Christ?

Mystici corporis