I wish this were not true, but it is. There is an inevitability to sin.
All men will sin because all men are fleshly and even those who are redeemed have not yet been finally redeemed. Our own natures will eventually produce sin. We are enticed by our own lust, James says (1:13-14). In that sense, we are our own worst enemies.
But Jesus notes that sometimes people also sin because they have been enticed to sin (Matthew 18:7-9). At times the bait is from the world system that offers something that seems irresistibly attractive. On other occasions, a trusted individual engages in ungodly behavior but does so in a way that makes it seem appropriate. And an undiscerning individual copies that sin and incurs his own condemnation or discipline from God. But Jesus warns that ones who entice others to engage in sin because of their own involvement with sin not only receive judgment for their sin, but a further judgment for leading others to sin (v. 7). We might call those judgments the two woes of temptation.
Then Jesus says that the one who habitually sins (stumbles) is wise to do radical amputation of the things that entice him to sin (vv. 8-9). If his sin is the result of what he sees, then pluck out his eye — that is remove the things that enter his mind through the gate of the eye. If the sin is the result of where he goes with his feet or what he does with his hands, then he should cut off his hands or feet — that is, cease practicing those things that produce sinful activities.
We often encourage people to “get radical” with the pervasive sins of their life as a means of growing in sanctification and progressing to Christlikeness. But Jesus teaches here that there is another reason to be radical with our sins — to keep others from sinning in similar ways and to keep us from experiencing compounded judgment.
This extreme removal of enticements to sin protect us from the judgment of God, but the amputation does even more than that. By removing the temptation from our own lives, we not only keep ourselves from sin, but we also do not tempt others to sin, and thereby avoid the judgment that comes as a result of leading them into sin.