Paul's expression of astonishment is actually a stinging rebuke: I am astonished that you are so quickly deserting the one who called you by the grace of Christ and are turning to a different gospel. The present tense of the verb deserting tells us that the Galatian Christians had not yet decisively carried out their desertion. They were just starting to turn around and leave. Paul's letter was designed to arrest them before they had gone too far. The one they were deserting was the one who had called them by the grace of Christ. While this may be read as a reference to Paul himself, similar references to God's call by his grace in Paul's life (1:15) and in the Galatians' experience (5:8) indicate that the reference is to God. Paul is stunned that people who had just recently experienced so much of God's miraculous power by his Spirit in their lives (3:1-5) would now turn away from him. They are turning their backs on God in order to follow a different gospel.
The content of this different gospel will become evident as we read the letter. But it is clear already that this gospel was not God-centered. It was drawing people away from God to focus on themselves. Preoccupation with racial identity, religious observance and ceremonial rituals was robbing them of their experience of God's grace expressed in Christ. The irony and tragedy of the situation was that in their pious pursuit of spiritual perfection (3:3) they were actually turning away from God.
The Galatian tragedy is a warning for us that not every quest for spirituality is in reality a quest for God. The emphasis in our day on "spirituality" and "spiritual formation" may be a way of finding God. But it may also be a way of running and hiding from God. When we are enticed by provocative books on New Age spirituality, we must remember that the Galatian Christians were trapped by a message that promised spiritual perfection but turned them away from God.
IVP New Testament Commentaries are made available by the generosity of InterVarsity Press.