And having in a readiness to revenge all disobedience, when your obedience is fulfilled.
Translate, 'Having ourselves (i:e., being) in readiness to exact punishment for all disobedience,' etc.
When your obedience ... He charitably assumes that the Corinthian church will act obediently; therefore he says "YOUR obedience." But as some will act otherwise, in order to give all an opportunity of joining the obedient, he waits (not prematurely exacting punishment) until the full number of those who obey Christ has been 'completed,' and the remainder have proved incorrigible. He had acted already so at Corinth (Acts 18:6-11: cf. Exodus 32:34; Matthew 13:28-30).