The expression Think of the devil and he will appear… as used in the passage,…

  Like a clock with the pendulum in full swing, the mind moves as fast as time. But we ought to mind our thoughts, for if they turn to be our enemies. They will be too many for us and will drag us down to ruin.

  But some people may say that they cannot help having bad thought even though they sting like vipers. That may be true, but the question is do they hate them or not? We cannot keep thieves from looking in at our windows, but if we open our doors to them and receive them joyfully, we are bad as they. We cannot help the birds flying over our heads; but we may keep them from building their nests in our hair. Vain thoughts will knock at the door but we must not open to them.

  Though bad and evil thoughts rise in our hearts, they must not be allowed to reign. He who turns a morsel over and over in his mouth does so because he likes the flavours, and he who meditates upon evil, loves it, and is ripe to commit it. think of the devil, and he will appear, turn your thoughts towards will and your hands will soon follow. Snails leave their slime behind them, and so do vain thoughts. An arrow may fly through the air, and level no trace, but an evil thought always leaves a trail like serpent.

  Where there is much traffic of bad thinking, there will be much mire and dirty. Every wave of wicked thought adds something to the corruption which rots upon the shore of life. It is dreadful to think that a vile imagination. Once indulged, gets the key of our minds, and get in again very easily, whether or not we let it in, and what may follow, no one knows,. Nurse evil on the laps of thought, and it will grow into a giant.

  Therefore, there is wisdom in watching every day, the thoughts and imaginations of our hearts. Good thoughts are blessed guests and should be welcomed, well fed, and much sought after, but bad thoughts must fly out as swiftly as they moved in.