she is united in him, in his body. Three aspects of the Church as the Body of Christ are to be more specifically noted: the unity of all her members with each other as a result of their union with Christ; Christ as head of the Body; and the Church as bride of Christ." The Catechism spells out the significance of each of these three aspects. To distinguish the Body of Christ in this sense from his physical body, the term "Mystical Body of Christ" is often used. This term was used as the first words, and so as the title, of the encyclical Mystici Corporis Christi of Pope Pius XII. In that document, Pope Pius XII in 1943 states, "the mystical Body of Christ... is the Catholic Church." But in 1964 the Catholic bishops gathered at the Second Vatican Council, while acknowledging that “full incorporation” in the Church required union with the Sovereign Pontiff, described various degrees of being “conjoined” or “related” to the Church including all persons of good will, which was not something new. The council's decree on Ecumenism stated that "all who have been justified by faith in Baptism are members of Christ's body" (3). That is, those who do not present an obstacle ("obex") to the reality of the Sacrament taking place, such as formal schism or formal heresy. Eastern Orthodoxy The Eastern Orthodox Church considers itself to be the body of Christ Paul of Tarsus speaks about in his letters. It considers itself to be sinless, since it is the body of Christ, but that its members are "fallible and sinful." It is also believed in Eastern Orthodoxy that the Eastern Orthodox Church is the "mystical body of Christ", in the sense that "mystical union with Christ is a reality in his Church". Protestantism In modern teachings, the "Body of Christ" is used by other Protestants to collectively describe believers in Christ, as opposed to only those who are members of the Catholic Church. In this sense, Christians are members of the universal body of Christ not because of identification with the institution of the Church, but through identification with Christ directly through faith. This theology is based on several passages in the Bible, including ,, , and , and . Jesus Christ is seen as the "head" of the body, which is the church, while the "members" of the body are seen as