The octave day of new birth

Today we celebrate Divine Mercy Sunday, which is also the Sunday of the Octave of Easter. This morning's Office of Readings presents to us words from St. Augustine's Eighth Sermon in octava Paschae given to the newly baptized:

I speak to you who have just been reborn in baptism, my little children in Christ... [Baptism] is a sacrament of new life which begins here and now with the forgiveness of all past sins, and will be brought to completion in the resurrection of the dead. You have been buried with Christ by baptism into death in order that, as Christ has risen from the dead, you also may walk in newness of life...

This is the octave day of your new birth. Today is fulfilled in you the sign of faith that was prefigured in the Old Testament by the circumcision of the flesh on the eight day after birth. When the Lord rose from the dead, he put off the mortality of the flesh; his risen body was still the same body, but it was no longer subject to death. By his resurrection he consecrated Sunday, or the Lord's day. Though the third after his passion, this day is the eighth after the Sabbath, and thus also the first day of the week.

And so your own hope of resurrection, though not yet realized, is sure and certain, because you have received the sacrament or sign of this reality, and have been given the pledge of the Spirit.

This is an octave. Augustine here demonstrates the great significance of the number eight as a sign of redemption and new life as well as resurrection, as our own resurrection is secured by Christ's, in whose body we are incorporated by way of our baptism by water and the Spirit. Baptism into Christ is thus intrinsically linked to resurrection.

It is not uncommon to find baptismal fonts that are octagonal in shape for this very reason, as we find in the ancient baptistery in Milan where St. Augustine himself was likely baptized:


As Augustine also references, the number eight also applies to why the Church observes the Lord's Day, Sunday, as the eighth day, a day of new creation and birth in Christ, which, as Augustine writes, will be brought to completion in the resurrection of the dead. The work of Redemption is of greater significance and splendor than that of the first Creation, as the Catechism points out (CCC 349):

But for us a new day has dawned: the day of Christ's Resurrection. The seventh day completes the first creation. The eighth day begins the new creation. Thus, the work of creation culminates in the greater work of redemption. The first creation finds its meaning and its summit in the new creation in Christ, the splendour of which surpasses that of the first creation.

And a blessed Pascha to my Eastern Orthodox readers!