Colin G. Kruse, "The Offender and the Offence in 2 Corinthians 2:5 and 7:12," The Evangelical Quarterly 60.2 (Apr.-June 1988): 129-139.
Colin Kruse summarises his article thus:
The argument of this article has been that the offender mentioned in 2 Corinthians 2:5 and 7:12 is best identified with the incestuous person mentioned in 1 Corinthians 5, provided that the offence involved is seen to have been a personal attack against Paul and his apostolic authority on the occasion of the latter’s interim visit to Corinth. It has been assumed that the disciplinary action taken by the church in response to Paul’s demands in the ‘severe’ letter succeeded in bringing the offender to repentance.
While the objections that have been raised against this identification can be dealt with satisfactorily, it must be admitted that the arguments presented in this article fall short of positive proof. However, the suggested identification is plausible and does enable us to make good sense of 2 Corinthians as a whole.