The Spirit Entities that work through John of God are deceased doctors as well as saints. About thirty Spirit Entities are known to work with and through John of God. Only one Entity may incorporate into John of God at a time, but thousands of good spirits are working around him. One Entity and the patron after which the Casa has been named is Saint Ignatius of Loyola. Other Entities are King Salomon, Chico Xavier, Dr Augusto de Almeida, Dr Jose Valdivino, Dr Oswaldo Cruz, Jose Pinteiado and many more. The Casa volunteers often are able to tell the difference between the various entities as they possess their distinctive manners as any human being would.
A painting in the Casa main hall of Jesus extending his arm above Saint Ignatius who guides John of God's hand performing an operation. Above John of God, two spirit doctors and next to him, people in meditation supporting the work.