How affectionately Paul appeals to them after the strong admonition given in the previous verse. Calling them ‘Brethren’, he shows that all he has said has had their best interests at heart, indeed he longs to see them free from the grip of false teaching and restored to Christ.
Paul does not ask any to do what he does not do himself. He sets the Galatians an example of openheartedness before requesting the same from them. Just as a father must be the first to show affection to a suspicious teenager, so a pastor must take the initiative to win back the trust of his flock when there is a breach between them.
As Calvin says, Paul is following the method he has recommended to Timothy, ‘Reprove, rebuke, exhort, with all long-suffering and doctrine’ – always in control. The pastor must exercise great patience towards the wayward, and if the time comes that an offender has to be put out of the church because of failure to repent after warning and further warning, it is not because the pastor has run out of patience and has no more long-suffering left to show, but because the word of God requires that he exercise the final solemn step of discipline.