This world was created perfectly, and so were the first man and woman.  But since sin gained a foothold, it has become a deadly endemic disease affecting everybody (Romans 5:12).  It is like a virus, which infects and corrupts its victim and then multiplies within the person before being widely spread to others.  The consequences of sin are seen everywhere, and temptations to sin abound (1 John 2:16).  But although Jesus knew the depraved state of human society, He intentionally came to bring God’s light into a dark world (John 3:19-21), to bring people back to God (1 Peter 3:18).  

Jesus had very strong words for any who presumed that the normality of wickedness is acceptable to God (Habakkuk 1:13).  By saying ‘woe’, the Lord was issuing a serious warning against the danger of real disaster for those who had no conscience about passing on the virus of sin to others.  The word translated as ‘stumble’ gives us ‘scandalise’ which means to morally shock or ‘encourage people to sin’.  It is also used by sailors to describe a way of derigging sails so that the boat cannot be propelled by the wind.  So, to cause people to stumble is to strike at the root of their moral conscience, allowing it to be overwhelmed, so that sinning becomes normal - with no power to live according to God’s purpose.

Perhaps referring to Judas Iscariot who facilitated the arrest and crucifixion of Jesus (John 6:70), the Master said that the endemic nature of sin was no excuse for individuals infecting others or making matters worse.  Rarely does Jesus express such condemnation of those who were supposed to be God’s people and yet whose sin contaminates others; especially 'little ones' (who might either be children or those young in the faith).  The fact that the 'grown up world' is corrupt is no excuse to corrupt others.

These powerful warnings to the disciples need to sink into our hearts too.  Selfishness and carelessness are as dangerous as evil wilfulness and malice (Mark 7:20-23).  Yet the sad fact is that no believer, including those in leadership, has succeeded in being totally perfect in this matter.  This warning of Christ's great displeasure is intended to make us believers stop and think, repent and seek His mercy.  Past sins must not be repeated, and the harm caused to 'little ones' must be taken seriously.  It is a very high standard, but without it we will easily descend into a pit of sinful viral relativism - where the clear call of the gospel is obscured by the moral mess created by self-obsessed believers.