Is it true that all validly baptized Christians are part of the Body of Christ?

[outremer]

In an letter to the Global Christian Forum, Pope Francis stated, “May the martyrs of today, belonging to many Christian traditions, help us to understand that all the baptised are members of the same Body of Christ, his Church.”

What is the basis for all validly baptized Christians belonging to the “same” Body of Christ? Thank you for your time.

Source: MESSAGE OF HIS HOLINESS POPE FRANCIS
ON THE OCCASION OF THE GLOBAL CHRISTIAN FORUM

 

[Fr.Charles_Grondin]

Catechism of the Catholic Church:

The sacramental bond of the unity of Christians

**1271 **Baptism constitutes the foundation of communion among all Christians, including those who are not yet in full communion with the Catholic Church: “For men who believe in Christ and have been properly baptized are put in some, though imperfect, communion with the Catholic Church. Justified by faith in Baptism, [they] are incorporated into Christ; they therefore have a right to be called Christians, and with good reason are accepted as brothers by the children of the Catholic Church.” “Baptism therefore constitutes the sacramental bond of unity existing among all who through it are reborn.”

Lumen Gentium:

1. The Church recognizes that in many ways she is linked with those who, being baptized, are honored with the name of Christian, though they do not profess the faith in its entirety or do not preserve unity of communion with the successor of Peter…They are consecrated by baptism, in which they are united with Christ… Likewise we can say that in some real way they are joined with us in the Holy Spirit, for to them too He gives His gifts and graces whereby He is operative among them with His sanctifying power. Some indeed He has strengthened to the extent of the shedding of their blood. In all of Christ’s disciples the Spirit arouses the desire to be peacefully united, in the manner determined by Christ, as one flock under one shepherd, and He prompts them to pursue this end.

Decree of Ecumenism:

1. …The children who are born into these Communities and who grow up believing in Christ cannot be accused of the sin involved in the separation, and the Catholic Church embraces upon them as brothers, with respect and affection. For men who believe in Christ and have been truly baptized are in communion with the Catholic Church even though this communion is imperfect.