This Proclamation of the Birth of Christ comes from the Roman Martyrology, the official listing of the saints celebrated by the Roman Rite of the Catholic Church. Traditionally, it has been read on Christmas Eve, before the celebration of Midnight Mass. It situates the Nativity of Christ within the context of salvation history, making reference not only to biblical events but also to the Greek and Roman worlds. The coming of Christ at Christmas, then, is seen as the summit of both sacred and secular history.
In the 1980's, Pope John Paul II restored the Proclamation of the Birth of Christ to the papal celebration of Midnight Mass. (It had been removed during the reform of the liturgy.) Many parishes have followed the Holy Father's lead.
The text below is a translation approved for use in the United States; to avoid the appearance of fundamentalism, it substitutes "unknown ages" and "several thousand years" for specific figures given in the Traditional Proclamation of the Birth of Christ.
Proclamation of the Birth of Christ
Today, the twenty-fifth day of December,
unknown ages from the time when God created the heavens and the earth
and then formed man and woman in his own image.
Several thousand years after the flood,
when God made the rainbow shine forth as a sign of the covenant.
Twenty-one centuries from the time of Abraham and Sarah;
thirteen centuries after Moses led the people of Israel out of Egypt.
Eleven hundred years from the time of Ruth and the Judges;
one thousand years from the anointing of David as king;
in the sixty-fifth week according to the prophecy of Daniel.
In the one hundred and ninety-fourth Olympiad;
the seven hundred and fifty-second year from the foundation of the city of Rome.
The forty-second year of the reign of Octavian Augustus;
the whole world being at peace,
Jesus Christ, eternal God and Son of the eternal Father,
desiring to sanctify the world by his most merciful coming,
being conceived by the Holy Spirit,
and nine months having passed since his conception,
was born in Bethlehem of Judea of the Virgin Mary.
Today is the nativity of our Lord Jesus Christ according to the flesh.