## What we say ##

"We" refers to Paul's ministry team. (See: [[rc://en/ta/man/translate/figs-exclusive]])

## we say by letter...is the same we as will do when we are there ##

Paul is stating that he seeks to live by the instructions he writes.

## to classify or compare  ##

"to rank or compare"

## have no insight ##

"show their ignorance"  or "show their lack of discernment."