The primary task of ministry
Purves tells us that Christian ministry is our participation in what Jesus is doing. Thus the primary task of our ministry is to bear witness to Jesus.
In that regard, Purves references the Isenheim altarpiece painting by Matthias Grunewald (shown at left). Note the hands in the painting. Our ministry is typified by the hands of John the Baptist (at right) who directs our gaze away from himself to Jesus. At John's right hand are the words (in Latin) of John 3:30: "He must increase, but I must decrease."
Purves comments further on the painting:
We should note the other hands in the painting. The primary direction is to look to the crucified Jesus. His enlarged hands show the agony of his atoning death for us. Then there are the enlarged praying hands of Mary Magdalene and the enlarged comforting hands of the apostle John. The other hand of the Baptist holds the open Bible. Even the Lamb at the foot of the cross is holding the Communion cup into which its own blood is dripping...
Bearing witness to Jesus is central because Jesus is the content of Christian faith, not as abstract doctrine but as a present, living and acting Lord in the freedom of his love and in the power of the Spirit. Our job is to bear witness not only to the past ministry of our Lord but also to his contemporaneous presence and act and to the horizon of promise and hope that his parousia opens up for us.Indeed, Christian ministry is all about Jesus - who he is, what he has done, what he is now doing, and what he will yet do for our salvation. It's a great joy and privilege to participate in his ministry, which flows from the Father, through Jesus, in the Spirit. We are included!