2 Corinthians 10:12

‘For we are not bold to number or compare ourselves with certain of them that commend themselves: but they themselves, measuring themselves by themselves, and comparing themselves with themselves, are without understanding.'

For he uses different measurements from them. He has no intention of boldly comparing himself with these men whose only recommendation was that they commended themselves by the simple expedient of commending each other, with the other then returning the compliment. Nor of numbering himself with them. He will not degrade himself by implying that they are of equal status with himself. They are not. They are such that they must be discredited. They look at each other, and exalt each other, thereby also, by reciprocation, exalting themselves, for they measure themselves against each other, and pat each other on the back. In so behaving they reveal their lack of understanding. They are saying in effect, ‘we all say that we are wonderful and so it must be true'. They fail to recognise that they are propping each other up nonsensically, and that the measure that they use is unreliable. That they are behaving foolishly. He might well have pointed out that ‘self-commendation is no recommendation'.