finishing of which some ascribe to Pope
Gelasius I., others more probably to Leo I., though the ground was
doubtless the work of their predecessors,) this festival is called
the Octave of our Lord's Nativity. The same title is given to it in
the Latin calendar (or rather collection of the gospels read at Mass
throughout the year) written above 900 years ago, presented to the
public by F. John Fronteau, regular canon of saint Genevieve's at
Paris, and by Leo Allatius. The inference which Baillet draws from
thence that the mystery of our Lord's circumcision was not then
commemorated in the office of this day, is a notorious mistake. For
Thomassin takes notice from Ivo of Chartres, that the word Octave
here implies the circumcision of our Lord, which was performed on
the eighth day after his birth; and in the above mentioned
Sacramentary express mention is made of the circumcision in the
Secret of the Mass. In F. Froubeau's calendar the gospel read on
this day is the history of the circumcision given, by St. Luke. An
old Vatican MS. copy of St. Gregory's Sacramentary and that of
Usuard's Martyrology kept at St. Germain des-Pres, express both the
titles of the Octave day and of the circumcision.

Durandus in the 13th century, (Ration. offic. l. 6, c. 15,) John
Beleth, a theologian of Paris, (c. 71,) and several missals of the
middle ages prescribe two masses to be said on this day, one on the
circumcision, the other on the B. Virgin Mary. Micrologus (c. 39)
assigns this reason, that as the B. Virgin, who had so great a share
in the birth of Christ, could not be mentioned in that solemn
office, therefore a commemoration of her is deferred to the Octave
day. The second Mass is now abolished: but in a great part of the
office a regard is had to the B. Virgin. In F. Fronteau's Roman
calendar, after the title of the Octave is added, _Natale S. Mariae_
for which Dom Martenne would have us read _S. Martinae_; but without
grounds. For, as Pope Benedict XIV. observes, (Comment. de Festis
Domini, c. 1,) the original unquestionably means a festival of the
B. Virgin Mary. The word _Natale_, which was used originally for the
birth-day of the emperors, was afterwards taken for any annual
feast.
2. Gen. xvii.
3. Grounding their opinion on Gen. xvii. 14, &c.
4. Luke i. 31.
5. Matt. i. 21.
6. Phil.