Woe is a slightly old-fashioned English word.  It means, 'grief is coming' which is a fair translation of the Greek word used here.  It is both a prediction and a warning.  This 'woe' is the other side of the coin to the 'blessings' in verse 20.  There, the poor who seek God's kingdom are satisfied.  Here, the rich seem to be self-satisfied; they have already reached the climax of contentment and there is nothing more for them.  Like the rich fool (Luke 12:15-21), everybody leaves everything when they die: the more they have, the more they leave.  

There is a parallel here with what Jesus said about the arrogant religious leaders who publicly flaunted their holiness by what they did.  Jesus said that in advertising their piety to gain the approval of others, they had already had their reward (Matthew 6:2; Matthew 6:5; Matthew 6:16) and God will give them nothing.  Likewise those who trust in their riches will have nothing but grief in eternity.

It is not wrong to have wealth, but it is wrong to make it the focus of life and to believe that it brings happiness and safety.   Security is important; but can we create it and keep it?  Surrounding ourselves with expensive possessions may give the illusion of safety and the power to control our destiny, but they are no way to God.  Jesus said that we cannot serve two masters: either we serve money, possessions and all that they promise, or we serve God (Luke 16:13).  Our attitude to what we possess exposes the motives of our hearts.  Either we treat them like toys - to please us and make us feel good; or we use them like tools for the Glory of God and under His command (1 Timothy 6:17-19).

In a world where we are taught to want more and get more, Jesus' words have a cool chill about them.  They are a serious warning about how to invest for eternity, although they are considered foolish by those who have no ambitions beyond the grave.  But Jesus' words should also warm the hearts of those who seek God's Kingdom and righteousness: He will provide for them sufficiently in this life (Matthew 6:33), and abundantly in the next.  It may be time to take a personal stance against the greed of business, the financial power of professionalism and against business practices which are not clearly righteous.  Your stand may help others who instinctively feel that greed is wrong and know they ought to be rich towards God (Luke 12:20-21), but do not know how to get out of the cycle of ambition or the lust for more.  The answer is only found in Jesus, whose love and comfort completely satisfies in this life and the next. www.crosscheck.org.uk may give them the starting point they seek.