1 Corinthians 4:6

Now these things, brethren, I have in a figure transferred to myself and Apollos for your sakes; that in us ye might learn not to go beyond the things which are written; that no one of you be puffed up for the one against the other. [Though neither Paul nor Apollos had headed a faction in Corinth, Paul has spoken in this Epistle as though they had done this, and that he might spare the feelings of the real leaders in faction he had put himself and Apollos in their places, and had shown the heinousness of their supposed conduct as reproved by many passages of Scripture. He had done this that the Corinthians, seeing the evil of such a thing even in an apostle, might see it more plainly in their little local party leaders, and might not boast themselves of any one leader to the disparagement of another. We may be sure that those who were puffing themselves up in one, were correspondingly busy traducing the other.]