Literally, “empty words,” such as words suggesting that the sins enumerated (vs. 3-5) would not keep one out of the kingdom. Heresies were already threatening the infant church. Paul is warning against the deceptive manner in which false teachers were insinuating themselves into the Christian community. For further general warnings about the deceptions that would divide the flock see Rom. 16:18; 1 Cor. 3:18; 2 Cor. 11:3; Col. 2:8; 2 Thess. 2:3, 4.