Ecclesiastes 10:8 says, He that diggeth a pit shall fall into it; and whoso breaketh an hedge, a serpent shall bite him.  I believe that Solomon is warning against trying to set a trap for others or breaking down long established boundaries.  When we attempt to trap others to do them harm, it is often going to backfire on us.  For one thing, if we are following the leadership of God, we are not going to be attempting to harm others, and if we are, ultimately this will cause us harm in the eyes of God.  Likewise, if we are attempting to take something that belongs to others, the same ultimate fate awaits us.  There are wars today where one country is trying to take what belongs to another, sometimes simply because they are more powerful and feel that they have a right to do this because of their might.  This is folly, or foolish thinking according to the wisdom of God.  Verse nine says, Whoso removeth stones shall be hurt therewith; and he that cleaveth wood shall be endangered thereby.  I believe this must be a warning to work with care and wisdom.  If we just randomly or carelessly remove stones from a wall, or tear down established laws just because of a dislike for them, then we set ourselves up to be harmed.  If we are cutting wood, it is better to use a sharp axe.  I believe we can apply this to anything we are doing.  We are better off using well maintained tools.  One of the tools we have to combat the evil in the world is the Bible, and if our knowledge of it becomes blunt, we are less able to shape our lives in obedience to God's will. We must live our lives wisely in all we do.  Verse ten expands the thought, stating,  If the iron be blunt, and he do not whet the edge, then must he put to more strength: but wisdom is profitable to direct.  We can work wisely or forcefully by our own strength.  We may feel that we can power through on our own strength, but we are better off to be directed by wisdom, the leadership of God.  Verse eleven says,  Surely the serpent will bite without enchantment; and a babbler is no better.  I believe Solomon is warning us against idle talk or gossip, which he compares to a serpent.  We may not even understand how many people our blabbering, speaking without real knowledge, may harm.