Expositor's Bible Commentary Commentary Matthew 18:9

"And if thine eye causeth thee to stumble, pluck it out, and cast it from thee: it is good for thee to enter into life with one eye, rather than having two eyes to be cast into the hell of fire." — Matthew 18:9 (ASV)

Jesus now abandons denunciation of the world’s causing his disciples to stumble and tells his disciples they may prove to be not only victims but aggressors. Certain attitudes nurtured by them toward other believers could also be sinful; thus, instead of being enticed to sin by outsiders, they would cause their own stumbling. Perhaps the particular believer-to-believer attitude that most needs rooting out is pride; thus vv.8–9 prepare for v.10.