Unskilled in speaking: the word unskilled means “untrained” (New Revised Standard Version). Paul was not an expert in this area. In speaking refers specifically to “public speaking” (Anchor Bible). The meaning is clearly expressed in God’s New Covenant, “Granted that I lack skill as an orator.” Or a better model in some languages may be “It is true that I do not speak well before crowds [or, other people].” See comments on 10.10.

Not in knowledge: the translation of these words will depend to some extent on the way the first part of this verse has been rendered. But in many cases a verbal expression will be called for: “I may not speak as well as they do, but I know as much as they do” or “my knowledge is not inferior to theirs, even if my public speaking is.”

In every way and in all things: according to both Revised Standard Version and Good News Translation, Paul has made plain his knowledge in every way and in all things to the Corinthians. Another interpretation is possible, however. The words in all things may be masculine, that is, “among all men.” If this second interpretation is followed, the sense of 11.6b is that expressed in God’s New Covenant: “And that is a fact which we have made evident in every way among men, wherever they may be, through what we are in our relations with you.”

Quoted with permission from Omanson, Roger L. and Ellingworth, Paul. A Handbook on Paul’s Second Letter to the Corinthians. (UBS Handbook Series). New York: UBS, 1993. For this and other handbooks for translators see here .