One particular challenge for renewing catechesis is that it seems to take place for only a limited period of time—usually early in a Christian's life of faith, or in the adolescent or teen years—and comes to a definite end. As such, catechesis can have a kind of "one and done" feel. You go through it, whether for a few months or a few years, and then baptism or confirmation marks a definite endpoint, after which a Christian no longer needs catechizing.
This is of course a profound misunderstanding of catechesis. But the challenge remains for how to think structurally about catechesis as a long-term or ongoing task. We need to think foundationally about how we might have adults who privilege the process or ongoing catechesis, so that we can avoid what Luther identified as the hubris of thinking we can get "beyond" the catechism.
In the early church, the newly baptized would undergo a weeklong immersion—"mystagogy"—in which they were instructed in the sacramental and liturgical life of the church, from which they would have been barred from participation until that point. But still, this was only a week.
Interestingly, another rite surfaced around the fifth century, likely in Rome, which seems to have had in view the ongoing catechesis of new, but not brand new, Christians.
"Pascha Annotinum" was a liturgical rite whose purpose was to celebrate the one-year anniversary of an Easter baptism. It took place around Easter—some scholars thing just before, some think after—and they seem to address those who were still "infants" in the faith, but who needed to be fully "weaned." According to an antiquarian textbook, evidence for this practice can be found in twelfth-century clerics such as Honorius of Augustodunensis (Autun), the liturgist and canonist William Durandus, and Jean Beleth, and then adopted by seventeenth- and eighteenth-century liturgists like Cardinal Thomasius, Edmund Martene, and Jean Mabillon. There is also a reference to this rite in the Gregorian Sacramentary.
One of the earliest pieces of evidence, however, comes from Sermon 73 of Peter Chrysologus (ca. 380 - 450), bishop of Ravenna in northern Italy during the mid fifth century. We don't know much about the specifics of this rite by this early, but it seems quite similar in appearances and emphases.
This sermon begins with reference to the present Easter season. The preacher here gives some clues about the "time" of this event, and its connection to the Passover. A multitude of times are overlaid: the first Passover in Egypt, Christ's Passover, the present Passover, the church year more broadly ("the year of the Lord" progressing through the seasons). The present moment is closely linked with Christ.
Today’s feast, brothers, does not connect the old with the new, nor does it keep the flesh of the lamb for tomorrow, but while it makes the past a partner with the present in solemn devotion, and joins our Passover with the Passover that returns, it weans the infants newly regenerated, because as the Apostle says, “The old has passed away, [and] see all things have been made new.” The year of the Lord progresses through seasons, it does not grow old, since it repeats its cycle for as long as it takes to lead us to the day of recompense. (73.1)
He then remarks on the two-fold dynamic implicit in this weaning imagery.
Today’s solemnity of Easter now withdraws from milk those whom it bore earlier, so that they might be strengthened by eating more solid food and be made into the perfect man of Christ. (73.1)
The milk is taken away and the solid food is introduced. In Reformation parlance, there is a time to put aside the small catechism (at least in terms of one educates himself), and take up the larger catechism. There is a time to grow more serious in one's education in the school of Christ.
What is especially noticeable about the imagery of the sermon is its repeated play on the language of weaning. Christians are newly born at baptism, and so, like newborns, are first nourished by the milk from mother church. But after a year, not unlike natural infants, like they are weaned from the milk, and are ready to partake of more solid food.
Chrysologus recalls the joyful occasions in biblical history when barren mothers rejoiced over the weaning of children: Sarah rejoicing over Isaac (Gen. 21:8), Anna over Samuel (1 Sam. 10). So too does the "Virgin Mother," the church, rejoice over the weaning of these new babes. If the biblical witness testifies to these women rejoicing,
all the more is it right for us to offer a sacrifice of praise, to pay our vows, and to present sweet incense and offerings, as ample as any holocaust, to God the Father, since the Virgin Mother presents to the Father children from throughout the whole world who have been nourished and weaned and are as numerous as the stars of the sky, so that the words of the prophet might be fulfilled: “You will bless the crown of the year with your bounty, and your fields will be full of a fertile harvest” (Ps. 65:11). (73.2)
The church rejoices and give thanks for the growth of believers. Such praise is indeed a thank-offering, a eucharistia, to the Father, as a mother rejoicing over the birth and growth of her children.
Peter concludes by offering his fullest exposition of the weaning metaphor. He distinguishes between the "recently born" (those who would have been baptized at the present Easter), those who have been earlier (more seasoned saints), and, finally, those to whom he is now addressing, those in between infancy and adulthood. Each phase has slightly different focus:
Consequently, while the recently born are trained in what they ought to do, and at the same time those who were born earlier are instructed in how much thanks they owe to God on account of their being perfected, those who have just been born cleave to the neck and completely devote themselves to clinging to the breasts of their Mother the Church, they swallow the food of innocence in their tender throats, give thought to extending their arms in holy work, and strive to make their trembling steps firm on the journey of faith.
Finally, Peter considers how the church should care for those in the in-between stage, somewhat advanced in the faith, and now needing to be weaned.
Are those who have been nourished now to be abandoned? Shouldn’t they instead be governed by the care of the Father, by the hand of the Father, and by the will of the Father, and likewise be protected by the counsel of the Mother and by the faith of the Mother, such that they take and make off with not merely human things but even the saving divine wisdom? (73.3)
Peter's homily is a call both to the young Christians to seek to "feed themselves" through the nourishment of their Father and Mother. But it is also a summons to the church to make allowance for these kinds of Christians. For in fact, this is a majority of the kinds of Christians that make up the church, especially by the fifth century, but even more so as Christendom began to settle in place.
Much the same could be said for today. I've been struck recently by J. I. Packer's laments of the short supply of literature aimed at the adult catechesis level. We have plenty of evangelistic writing for new Christians, and plenty of specialist literature for pastors and academics. But what about those in between? What about those who have been Christians for some time but need quality resources for growing deeper? This is the kind of thing C. S. Lewis did so wonderfully, and for which many Christians today, new and old, are so grateful.
But in addition to good literature, what kinds of structures are in place that foster this kind of continuing growth? What rites are there that aim towards maturing faith? Where are the adult catechists who are trained and can equip congregations for this work? Such is the need our time.