10. letters—implying that there had been already more letters of Paul received by the Corinthians than the one we have, namely, First Corinthians; and that they contained strong reproofs.
say they—Greek, "says one," "such a one" (2Co 10:11) seems to point to some definite individual. Compare Ga 5:10; a similar slanderer was in the Galatian Church.
weak—(2Co 12:7; 1Co 2:3). There was nothing of majesty or authority in his manner; he bore himself tremblingly among them, whereas the false teachers spoke with authoritative bearing and language.