50 As has already been mentioned, also among our divided brethren many honor and celebrate the Mother of the Lord, especially among the Orientals. It is a Marian light cast upon ecumenism. In particular, I wish to mention once more that during the Marian Year there will occur the Millennium of the Baptism of Saint Vladimir, Grand Duke of Kiev . This marked the beginning of Christianity in the territories of what was then called Rus', and subsequently in other territories of Eastern Europe. In this way, through the work of evangelization, Christianity spread beyond Europe, as far as the northern territories of the Asian continent. We would therefore like, especially during this Year, to join in prayer with all those who are celebrating the Millennium of this Baptism, both Orthodox and Catholics, repeating and confirming with the Council those sentiments of joy and comfort that "the Easterners...with ardent emotion and devout mind concur in reverencing the Mother of God, ever Virgin." Even though we are still experiencing the painful effects of the separation which took place some decades later , we can say that in the presence of the Mother of Christ we feel that we are true brothers and sisters within that messianic People, which is called to be the one family of God on earth. As I announced at the beginning of the New Year "We desire to reconfirm this universal inheritance of all the Sons and daughters of this earth." In announcing the Year of Mary, I also indicated that it will end next year on the Solemnity of the Assumption of the Blessed Virgin into heaven, in order to emphasize the "great sign in heaven" spoken of by the Apocalypse. In this way we also wish to respond to the exhortation of the Council, which looks to Mary as "a sign of sure hope and solace for the pilgrim People of God." And the Council expresses this exhortation in the following words: "Let the entire body of the faithful pour forth persevering prayer to the Mother of God and Mother of mankind. Let them implore that she who aided the beginning of the Church by her prayers may now, exalted as she is in heaven above all the saints and angels, intercede with her Son in the fellowship of all the saints. May she do so until all the peoples of the human family, whether they are honored with the name of Christian or whether they still do not know their Savior, are happily gathered together in peace and harmony into the one People of God, for the glory of the Most Holy and Undivided Trinity."
Source: Redemptoris Mater (Vatican.va)