Today, we turn to Paul’s second letter to the Corinthian saints. However, it is really not the second letter because it appears that Paul wrote a letter to the Corinthian church even before 1 Corinthians (see 1 Cor 5:9). Also it is not clear that 2nd Corinthians is only one letter; it may be a composite of multiple letters by Paul to the Corinthian saints. Margaret MacDonald, in the Oxford Bible Commentary, explains:
It is a generally held view today [by scholars] that 2 Corinthians is made up of more than one of Paul’s letters. Although, there is no MS [manuscript] evidence to support this theory, there are several problems in the text as we have it which raise the question of its unity. Among the more serious difficulties is the sharp break between the conciliatory tone of chs. 1-9 and the harsh, sarcastic tone of chs. 10-13.
Authorship: Paul is the author of this letter (or composite of multiple letters); it is considered authentic by most scholars. “In form and style 2 Corinthians closely resembles Paul’s other works, and its authenticity has not been questioned. However, the language and content of 2 Cor 6:4-7:1 have struck many as difficult to reconcile with Paul’s other writings and, therefore, this passage has often been viewed as an interpolation.”