The law of praying
Sometime in the fifth century, St Prosper of Aquitaine wrote:
Let us consider the sacraments of priestly prayers, which having been handed down by the apostles are celebrated uniformly throughout the whole world and in every Catholic Church so that the law of praying might establish the law of believing.
At some point, this began to be summarised by the catchier phrase Lex orandi, lex credendi — the law of praying is the law of believing. That is to say, the prayers that the Church has developed over the centuries tell us what we are meant to believe, and are an authoritative source of her teaching. This is illustrated best of all in the most important and central prayer of the Church, the Mass. And, of all the prayers the Mass contains, none tells us so much about what the Church believes about God and herself than the Canon. The name of this section, the ‘Canon’ reflects precisely this principle. A canon is a rule or principle. The Canon of the Mass is that unchanging part of every Mass, which forms not only the rule of how the priest must pray at Mass, but also a rule of faith for all Christians. Different rites have their own Eucharistic prayers; the Roman Canon has been at the heart of every Mass celebrated in the Western Church for over 1500 years.
The Canon that we say…remains as it was in the days of Gregory I (c. 600AD), and that goes back far behind his time till its origin is lost in the mists that hang over the first centuries when the Roman Christians met together to “do the things the Lord commanded at appointed times” (Letter of St Clement c. 70AD)… The Canon stands out firm and unchanging in the midst of an ever-developing rite, the centre and nucleus of the whole liturgy, stretching back with its strange and archaic formulæ through all the centuries of church history, to the days when the great Roman Cæsar was lord of the world and the little community of Christians stood around their bishop while they “sang a hymn to Christ as to a God before day-break” (Pliny the Younger c. 100AD). Then the bishop lifted up his hands over the bread and wine, “gave thanks and glory to the Father of all through his Son and the Holy Ghost, and made the Eucharist” (Apology of St Justin Martyr c. 155AD). So that of all liturgical prayers in the Christian world no one is more ancient nor more venerable than the Canon of the Roman Mass. (Fr Adrian Fortescue)
Over the summer, we will look at a section of this prayer each week, and learn what the ‘law of praying’ has to teach us about what we believe.