I believe Charles Dickens has portrayed Murdstone as a villian from the very start. A key factor that leads me to believe he is a villian is the quote, "with his ill-omened black eyes." This quote portrays Murdstone as sinister and mysterious. Another reason that one could see the character as evil is the fact that the first four letters of his name spell "Murd", which  sounds short for murder. Also, Mr. Murdstone drives fear into David's mind, because meeting someone you don't know can be overwhelming.