1 Corinthians 4:18

It is clear from this that what was being said was that Paul and his companions were weak, while the Corinthians were strong.

Some of the Corinthians were angry that Paul had not come to them, not because they wanted him to but because they were proud and imagined that Paul thought they were unworthy of a visit. In fact, Paul wanted to go but had more important things to do.

"Now some are puffed up, as though I were not coming unto you." For there he glances both at them and at certain others, casting down their highmindedness: since the love of preeminence is in fault, when men abuse the absence of their teacher for their own self-will. For when he addresses himself unto the people, observe how he does it by way of appeal to their sense of shame; when unto the originators of the mischief, his manner is more vehement. Thus unto the former he saith, "We are the offscouring of all:" and soothing them he saith, "Not to shame you I write these things;" but to the latter, "Now as though I were not coming to you, some are puffed up;" shewing that their self-will argued a childish turn of mind. For so boys in the absence of their master wax more negligent. This then is one thing here indicated; and another is that his presence was sufficient for their correction. For as the presence of a lion makes all living creatures shrink away, so also does that of Paul the corrupters of the Church.