1st January, The Circumcision of Our Lord and Octave of the Nativity

The Circumcision of Our Lord and Octave of the Nativity

In the Liturgy of to-day three feasts are really included. The first, that which was known in the ancient sacramentaries as "On the octave-day of our Lord". So the Mass is largely borrowed from those of Christmas.

By the second feast we are reminded that it is to Mary, after almighty God, that we owe our Lord Himself. For this reason, formerly a second Mass was celebrated in the basilica of St. Mary Major, in honour of the Mother of God. Some traces of this Mass remain in the Collect, Secret, and Postcommunion which are the same as in the votive mass of the Blessed Virgin Mary. The psalms at Vespers are also the same as on the feasts of our Lady.

The third feast is the Circumcision which has been kept since the sixth century. Moses commanded that all the young Israelites should undergo this rite on the eighth day after birth (Gospel). It is a type of Baptism by which a man is spiritually circumcised. "See," says St. Ambrose, "how the whole sequence of the Old Law foreshadowed that which was to come; for circumcision signifies the blotting out of sins. He who is spiritually circumcised by the rooting up of his vices is judged worthy of the Lord's favour." While speaking of the first drops of His sacred Blood that our Redeemer shed for the cleansing of our souls, the Church emphasises the thought of the cutting out of all that is evil in us. "Jesus Christ ... gave Himself for us that He might redeem us from all iniquity and cleanse us" (Epistle). "O Lord ... cleanse us by these heavenly mysteries" (Secret). "May this communion, O Lord, purify us from sin" (Postcommunion).

Puer natus est nobis, et filius datus est nobis, cujus imperium super humerum ejus: et vocabitur nomen ejus, magni consilii Angelus. * Cantate Domino canticum novum: quia mirabilia fecit.
A child is born to us, and a Son is given to us, whose government is upon His shoulder: and His name shall be called the Angel of great counsel. * Sing ye to the Lord a new canticle : because He hath done wonderful things.
(Isaias 9:6 and Psalm 92:10 from the Introit of Mass)

Deus, qui salutis aeternae, beatae Mariae virginitate fecunda, humano generi praemia praestitisti: tribue, quaesumus: ut ipsam pro nobis intercedere sentiamus, per quam meruimus auctorem vitae suscipere, Dominum nostrum Jesum Christum Filium tuum.
O God, who by the fruitful virginity of blessed Mary hast bestowed upon the human race the rewards of eternal salvation: grant, we beseech Thee, that we may experience the intercession of her, through whom we have been made worthy to receive the author of life, Jesus Christ Thy Son, our Lord.

(Collect)

The continuation of the Holy Gospel according to St Luke

Et postquam consummati sunt dies octo ut circumcideretur vocatum est nomen eius Jesus quod vocatum est ab angelo priusquam in utero conciperetur.

And after eight days were accomplished, that the child should be circumcised, his name was called JESUS, which was called by the angel, before he was conceived in the womb.

(St Luke 2:21)

Magnum hereditatis mysterium: templum Dei factus est uterus nescientis virum: non est pollutus ex ea carnem assumens: omnes gentes venient, dicentes: Gloria tibi, Domine.

O mighty mystery of generation: the womb of her who knew not man is become the temple of God: He who takes flesh from her is not defiled: all nations shall come, and say: Glory be to Thee, O Lord.
(Magnificat Antiphon at Vespers)

Catholic Encyclopaedia on the Feast of the Circumcision: http://www.newadvent.org/cathen/03779a.htm