John Chrysostom

Then he comes to other illustrations again. And as above he alleged the examples of the Apostles and those of common custom and those of the priests, and his own, so also here having set forth those of the Olympic games and those of his own course, he again proceeds to the histories of the Old Testament. And because what he has to say will be somewhat unpleasing he makes his exhortation general, and discourses not only concerning the subject before him, but also generally concerning all the evils among the Corinthians. And in the case of the heathen games, "Know ye not?" saith he: but here, "For I would not, brethren, have you ignorant."

Now this he said, implying that they were not very well instructed in these things.