84 In a theocentric vision, we Christians already have a common Martyrology . This also includes the martyrs of our own century, more numerous than one might think, and it shows how, at a profound level, God preserves communion among the baptized in the supreme demand of faith, manifested in the sacrifice of life itself. The fact that one can die for the faith shows that other demands of the faith can also be met. I have already remarked, and with deep joy, how an imperfect but real communion is preserved and is growing at many levels of ecclesial life. I now add that this communion is already perfect in what we all consider the highest point of the life of grace, martyria unto death, the truest communion possible with Christ who shed his Blood, and by that sacrifice brings near those who once were far off (cf. Eph 2:13). While for all Christian communities the martyrs are the proof of the power of grace, they are not the only ones to bear witness to that power. Albeit in an invisible way, the communion between our Communities, even if still incomplete, is truly and solidly grounded in the full communion of the Saints—those who, at the end of a life faithful to grace, are in communion with Christ in glory. These Saints come from all the Churches and Ecclesial Communities which gave them entrance into the communion of salvation. When we speak of a common heritage, we must acknowledge as part of it not only the institutions, rites, means of salvation and the traditions which all the communities have preserved and by which they have been shaped, but first and foremost this reality of holiness. In the radiance of the "heritage of the saints" belonging to all Communities, the "dialogue of conversion" towards full and visible unity thus appears as a source of hope. This universal presence of the Saints is in fact a proof of the transcendent power of the Spirit. It is the sign and proof of God's victory over the forces of evil which divide humanity. As the liturgies sing: "You are glorified in your Saints, for their glory is the crowning of your gifts". Where there is a sincere desire to follow Christ, the Spirit is often able to pour out his grace in extraordinary ways. The experience of ecumenism has enabled us to understand this better. If, in the interior spiritual space described above, Communities are able truly to "be converted" to the quest for full and visible communion, God will do for them what he did for their Saints. He will overcome the obstacles inherited from the past and will lead Communities along his paths to where he wills: to the visible koinonia which is both praise of his glory and service of his plan of salvation.
Source: Ut Unum Sint (Vatican.va)