Note 7 at 2 Cor. 10:18: This is a wonderful truth which has many applications. But in context, Paul must be applying this to those who had opposed him. His argument against those who had questioned his authority was that they were "self-approved." They didn't have any proof of their claims to authority. They were commending themselves. Paul is saying only those whom God commends are truly approved. The Lord used miracles to verify authority (see note 8 at Acts 2:22, p. 580), and Paul had plenty of those (2 Cor. 12:12). His accusers had none.