When people talk about something they often exaggerate or diminish the facts. For example, when someone ate almost all of your favorite food and just a little of it is left, you might say "They ate it all!" or "There's nothing left!" Most people do not consider this to be a lie, but this really comes from the nature of untruthfulness. If you have not thrown off this nature, you may tell a lie serious enough to cause harm to somebody. Only when you fill your heart with truthfulness in even the slightest things, will you be able to reach the levels of perfect truthfulness.