2 Corinthians 1:23

Moreover, I call God for a record upon my soul
The apostle having asserted his stability, both as a minister and a Christian, which, with others, he had from God, appeals to him in the most solemn manner, in full form of an oath, for the truth of what he was about to say; and is all one as if he had said, I swear by the living God, the searcher of all hearts; I call upon him to attest what I say, and bear witness to my soul, that it is true,

that to spare you, I came not as yet unto Corinth;
however fickle, unstable, and inconstant, it may be insinuated to you I am, or you may take me to be, I do assure you in the name and presence of God, that the true reason of my not coming to you hitherto, since I gave you reason to expect me, was, that I might not be burdensome or chargeable to you; or I have delayed coming to you, hoping for a reformation among you, that when I do come, I may not come with a rod, and severely chastise you for the many disorders among you; that I might not use sharpness according to the power God has given me, in an extraordinary way, as an apostle, to punish for offences committed. Hence we learn, that an oath is a solemn appeal to God, and may be lawfully made in cases of moment and importance, as this of the apostle's was; whose character was traduced, and with which was connected the usefulness of his ministry; and it being an affair that could not be determined in any other way, and an oath being for confirmation, and to put an end to strife, he makes one in this serious and awful manner.