2 But I beseech you, that I may not be bold when I am present with that confidence, wherewith I think to be bold against some, which think of us as if we walked according to the flesh.
[AD 407] John Chrysostom on 2 Corinthians 10:1-2
"Now I Paul myself." Great emphasis, great weight is here. So he says elsewhere, "Behold I Paul say unto you;" and again, "As Paul the aged;" and again in another place, "Who lath been a succorer of many, and of me." So also here, "Now I Paul myself." This even is a great thing, that himself beseecheth; but that other is greater which he added, saying, "by the meekness and gentleness of Christ." For with the wish of greatly shaming them, he puts forward that "meekness and gentleness," making his entreaty in this way more forcible; as if he had said, 'Reverence the gentleness of Christ by which I beseech you.' And this he said, at the same time also showing that although they should lay ever so strong a necessity upon him, he himself is more inclined to this: it is from being meek, not from want of power, that he does not proceed against them: for Christ also did in like manner.

[AD 407] John Chrysostom on 2 Corinthians 10:1-2
"Who in your presence am lowly among you, but being absent am of good courage toward you." What, pray, is this? Surely he speaks in irony, using their speeches. For they said this, that 'when he is present indeed, he is worthy of no account, but poor and contemptible; but when absent, swells, and brags, and sets himself up against us, and threatens.' This at least he implies also afterwards, saying, "for his letters," say they, "are weighty, but his bodily presence is weak, and his speech of no account." He either then speaks in irony, manifesting great severity and saying, 'I, the base, I, the mean, when present, (as they say,) and when absent, lofty:' or else meaning that even though he should utter great things, it is not out of pride, but out of his confidence in them.

[AD 407] John Chrysostom on 2 Corinthians 10:1-2
"But I beseech you, that I may hot when present show courage with the confidence, wherewith I count to be bold against some which count of us as if we walked according to the flesh." Seest thou how great his indignation, and how complete his refutation of those sayings of theirs? For he saith, 'I beseech you, do not compel me to show that even present I am strong and have power.' For since they said that 'when absent, he is quite bold against us and exalteth himself,' he uses their very words, 'I beseech therefore that they compel me not to use my power.' For this is the meaning of, "the confidence." And he said not, 'wherewith I am prepared,' but 'wherewith I count.' 'For I have not yet resolved upon this; they however give me reason enough, but not even so do I wish it.' And yet he was doing this not to vindicate himself, but the Gospel. Now if where it was necessary to vindicate the Message, he is not harsh, but draws back and delays, and beseeches that there may be no such necessity; much more would he never have done any thing of the kind in his own vindication. 'Grant me then this favor,' he saith, 'that ye compel me not to show, that even when present I am able to be bold against whomsoever it may be necessary; that is, to chastise and punish them.' Seest thou how free he was from ambition, how he did nothing for display, since even where it was matter of necessity, he hesitates not to call the act, boldness. "For I beseech you," he says, "that I may not when present show courage with the confidence, wherewith I think to be bold" against some. For this especially is the part of a teacher, not to be hasty in taking vengeance, but to work a reformation, and ever to be reluctant and slow in his punishments. How, pray, does he describe those whom he threatens? "Those that count of us as though we walked according to the flesh:" for they accused him as a hypocrite, as wicked, as a boaster.

[AD 384] Ambrosiaster on 2 Corinthians 10:2
Paul is referring here to those who did not accept that his teaching was spiritual.