By Their Very Working...
One of the aporias that face theology of the sacraments in the West is how they bear fruit; when do they do what they say the do? In other words, is baptism administered by just anyone legitimate baptism? What if someone is rebaptised? What if the person baptizing doesn't belong to the church or doesn't use the proper rite, doesn't baptize in the name of the Father, Son, and Spirit? What if someone's baptized and doesn't go to church or even actively disbelieves the gospel? All these questions came together in a crisis of the church in fourth century North Africa. This collision of question and crisis more or less has created the problem the Reformers considered: by the act of the sacrament, do they by their very working do what they intend to do? Does baptism, for instance, just flat out save?
The answer the West has usually given is that baptism given in the proper form (therefore baptism in any other name isn't baptism) by anyone for whatever purpose is a valid baptism. That's the key. But it is not an effective baptism until the person believes it. And this is the basic position of this article. Though the Reformation position here espoused does correct some late medieval understandings of the sacrament's efficacy by their very working, but on the whole, the Reformation agrees with the west.
Dissent from this position comes in many ways: the original Baptist position in the Reformation did not deny the efficacy of baptism but the validity of its administration in infant form. Wesley was scandalized by the fact that slave traders and other folk walked about England baptized. To him, it was proof enough that the validity of baptism doesn't mean a thing.
These categories--'validity' and 'efficacy'--are important for understanding the sacraments and their administration. But they do deserve amplification and further integration. Especially because the article says most radical of all: baptism and other sacraments are there to be used. They are there to be used by faith. While pastors and others in charge of splashing their water, Christians should welcome again their baptism, rejoice in the gift of public forgiveness, and believe with their mouths! For as surely as the taste of wine stays in my mouth, I am a believer!!