The word this refers mainly to the previous verses, but the present tense I … write leaves open the possibility that Paul is also thinking of the severe things which he will write, for example, in chapter 5. I do not write this … may be expanded to “I do not write these things to make you ashamed.”

Make you ashamed: this phrase may also be rendered as “make you lose face” or “make black in the face.”

The phrase but to may be expanded to “but in order to.”

To admonish you (Good News Bible‘s “instruct”): the verb in the Greek text is uncertain, with manuscripts varying between “instructing” and “I instruct.” Most commentators prefer “instructing” because it makes a better contrast with “making ashamed” than with “I write” (Good News Bible). The not-making-ashamed and the instructing are both results of Paul’s writing. Admonish could also be rendered as “teach a lesson to” or “make you understand.”

My beloved children: this phrase may be expressed as a simile; for example, “as though you were my own dear children” or “as though you were my children whom I love very much.”

Quoted with permission from Ellingworth, Paul and Hatton, Howard A. A Handbook on Paul’s First Letter to the Corinthians, 2nd edition. (UBS Handbook Series). New York: UBS, 1985/1994. For this and other handbooks for translators see here .