Abstract
We have faced the problems of the identity in all respects, nowadays. And without exception the Catholic Church also has the problems, her "catholicitas" or universality. With this concern the participation of the Catholic Church in ecumenism, is a matter of great importance, for the cause of the structure of self-understanding or self-definition that would come to her identity. As far as the way of this movement, Ecumenism, should be centred in "dialogue", toward the unity of "theology (dogma)", seeking the unity of "liturgy". The self-understanding through these three dimensions; dialogues as ecumenism, theologies (ortho-doxis) of the church (e.g.: ecclesiologies) and liturgies as ortho-praxis of the church, would indicate that the church does not have catholicitas in and by herself. Therefore the two should not be considered as one and the same. Even though she is surely called the body of Christ who preexist.
