The natural implication of this phrase is that it has not been long since Paul was with the Galatians and they came to faith in Christ.1 In that case they are leaving the truths that he proclaimed but a short time after he proclaimed those truths to them. Alternatively, it could refer to the arrival of the false teachers.2 The Galatians are in the process of transferring their loyalty from God3 only a short while after the false teachers have arrived in their midst. Paul did not think they would be so easily or quickly deceived.4
6 I am astonished that you are so quickly deserting him who called you in the grace of Christ and are turning to a different gospel