John Gill Commentary 2 Corinthians 13:10

"For this cause I write these things while absent, that I may not when present deal sharply, according to the authority which the Lord gave me for building up, and not for casting down." — 2 Corinthians 13:10 (ASV)

Therefore I write these things being absent
Assuring them of his power and authority, expressing his concern for their welfare, earnestly desiring that they might be kept from evil, and perform good works; and that they might be in a more honourable, orderly, and comfortable situation, whilst he was absent from them, and before he came among them:

lest, being present, I should use sharpness ;
meaning severe reproofs and censures, or rather the exercise of the apostolic rod:

according to the power the Lord has given me, to edification, and
not to destruction ;
by striking persons dead, as Ananias and Sapphira were by Peter; or by delivering them up to Satan to have corporeal punishment inflicted on them, as were Hymenaeus and Philetus, and the incestuous person by the Apostle Paul; which, though it was for the destruction of the flesh, yet for the salvation of their souls, and for the good, use, and edification of the rest of the society, that they might take warning thereby, and shun the evils which were the occasion of such severity.