St. Teresa of Ávila's books are integral part of the Spanish Renaissance literature as well as Christian mysticism and Christian meditation practices. The Interior Castle written is widely considered to be one of the greatest works on spiritual development. This classic work attracts a new generation of St. Teresa of Avila readers. The Interior Castle is required reading for various courses and curriculums and is enjoyed reading for others. St. Teresa of Ávila she was canonized by Pope Gregory XV in 1622, forty years after her death. In 1970 she was named a Doctor of the Church by Pope Paul VI.