An article of mine on the subject of infant baptism and Reformation debates concerning the relationship between grace and the administration of the sacrament of baptism has just been published over on Reformation21.
In characterizing magisterial Reformed objections to the Roman Catholic understanding of baptism at the time of the Reformation, some commentators have often focused too narrowly upon the theme of baptismal efficacy. While firmly opposing notions of ex opere operato, few of the magisterial Reformers resisted the notion of baptismal efficacy as such, but rather insisted upon the necessity of faith for the reception and enjoyment of this efficacy, upon God’s freedom in the bestowal of his grace, and upon the Word-based character of the sacraments. If we mistakenly equate baptismal efficacy with an ex opere operato mode of efficacy, we are in danger of missing the fact that the magisterial Reformers presented a higher and more efficacious doctrine of baptism than their Roman Catholic interlocutors.It is at this juncture that the significance of the ‘when’ question should be recognized. The Roman Catholics related the grace of baptism to the performance of the rite itself. For them, the grace signified in baptism was a grace received through the performance of the rite. The answer to the ‘when’ question was ‘at the point of baptism itself.’ Yet the grace of baptism received through the ex opere operato performance of baptism–so powerfully efficacious at the time of the performance–swiftly lost its efficacy. The grace of baptism, once given, was radically at the mercy of the baptismal candidate’s subsequent behaviour. The Canons of Trent (Session XIV in particular) reveal that, the grace of baptism being easily forfeited by sinners who failed to persevere in it, it was necessary to supplement its grace with that of another sacrament–penance. Penance was the answer to the acute problem of post-baptismal sin and to the (temporally) limited efficacy of the grace of baptism. The result was the diminishment of baptismal grace within the sacramental economy: beyond giving an initial impetus, baptism was swiftly substituted for by other sources of grace.
Read the whole thing here.
Alastair's Adversaria 
It seems to me that Romans 6 emphasizes that baptism is about the fact that we have died to the old and we have become new through our union with Christ. It doesn’t seem to me that the focus is so much on the not-yet, but it is on the already. This has practical application when it comes to how he instructs believers to deal with sin. Because you are united to Christ through baptism “offer the parts of your body to him as instruments of righteousness” (Rom. 6:13).
Thanks for the comment, Bill. I wonder whether you are neglecting the importance of verse 5 in Paul’s argument. Our bodies are united with Christ’s in the likeness of his death and burial in anticipation and promise of being united with his body in his resurrection. In baptism my body is marked out in anticipation of future resurrection and my limbs and organs are rendered to God in recognition of the fact that those self-same body parts are destined for resurrection life. We reckon ourselves to be alive from the dead and act accordingly because we have a (bodily) share in Christ’s resurrection, a share sealed to us in baptism.
There certainly is a future dimension to our salvation as you mention, but I suggest that Paul does not disconnect our participation in Christ’s death from our participation in his resurrection in such a way that pushing the focus of our salvation primarily into the future. It seems to me that Paul is trying to reorient the thinking and the practice of these believers, so he wants them to think of themselves as a new creation, having experienced new life through their union with Christ in his death and resurrection. They have already entered into the blessings of Christ’s resurrection that will culminate in the resurrection of the body (1 Cor. 15:20-23). All this to say that I don’t see his reference to baptism as being primarily about the future. To sum up I think he is saying, How can you keep on sinning? You have already been united to Christ. Don’t you understand the realities that are set forth through your baptism? You have died and been raised with Christ, so you have a new life that is characterized by resurrection life.
The connection between verse 4 and verse 5 is important here, as is the underlying logic of the verses that follow. We walk in newness of life because we are certain that we shall be united with him in his resurrection. The logic of being baptized into his death is such that union with Christ in his death holds as its counterpart resurrection with him (verse 8).
As you know this is a disputed point in the commentators. Those who say that Paul’s reference to the future is “logical” meaning those who experience Christs death also experience his resurrection (Godet, Murray, Fitzmeyer, Cranfield, Kruse, etc.) and those who say that it refers to the final resurrection at the eschaton (Moo, Barrett, Calvin, etc.). Osborne says it could be both
“In reality, this is not an either-or. It is best to take this in an inaugurated sense, where our present resurrection to new life in Chirst (vs.4) is an anticipation of our final resurrection with him (vss. 8-10). It seems to me that hte “newness of life” that he is writing about is resurrection life that is already at work in us, so he writes in Colossians, Since, then, you have been raised with Christ, set your hearts on things above . . . ” (Col.3:1). See also Colossians 2:12, “. . . having been buried with him in baptism, in which you were also raised up with him through faith in the working of God, who raised him from the dead . . .” Kruse states it well
Paul says that if we have been united with Christ in the likeness of his death, we ‘will certainly also be united with him in a resurrection like his’ (italics added). To express this, the apostle uses the future tense of the verb ‘to be’, leaving open the possibility of two interpretations: (i) it can be construed as a logical future: those who have allowed themselves to be identified with Christ’s death in baptism will certainly also share his resurrection life now, or (ii) it can be construed as an eschatological future: those who have allowed themselves to be identified with Christ’s death in baptism now will be united with him in resurrection life on the last day. In the context of 6: 1-14, where the apostle, as well as exhorting his audience to offer themselves to God as instruments of righteousness, is also combating charges that his gospel promotes moral anarchy in the present time, the former appears more appropriate.
Kruse, Colin G. (2012-06-14). Paul’s Letter to the Romans (The Pillar New Testament Commentary) (p. 262). Wm. B. Eerdmans Publishing Co.. Kindle Edition.
My point is that I think Paul’s emphasis is on the decisiveness of our union with Christ in his death and resurrection makes it possible to live a life of obedient faith. I think this argues against seeing baptism as primarily about promise.
I think you are taking my use of the notion of ‘promise’ in a rather narrower sense than intended. The ‘promise’ isn’t only referring to the eschatological future, but also to that period of time that intervenes. The point is that baptism is primarily prospective, rather than retrospective, not that it is merely concerned with an eschatological horizon.
That said, the eschatological horizon is immensely significant in the Pauline logic. The present life in the Spirit is to be appreciated and appropriated precisely as a downpayment, guarantee, and reality-filled promise of eschatological resurrection life. The ‘already’ of our bodily life in the Spirit must be related to the ‘not-yet’, which is the resurrection of the body. The promissory aspect, properly understood, is of immense and central importance.
Alastair, I’ve only recently become paedobaptist after attending a Presbyterian seminary. I haven’t come across an article addressing “when the grace of baptism is received” before, which is obviously crucial (once someone thinks to ask the question). Request: could you write a similar article at a lay level? I don’t know where else to get a thoughtful answer in language people can understand.
Thanks for taking the time to comment, James. Unfortunately, I don’t have the time to write such an article at the moment (perhaps at some point in the future), but I would like to see someone else do so.
That’s what I figured. Doesn’t hurt to ask. I really enjoy your blog and podcast.