Your English: Idioms: truth and lies
The former UK Cabinet Secretary, Sir Robert Armstrong, is generally credited with bringing an interesting euphemism for lying into contemporary use. When asked at a trial in 1986 to explain the difference between a lie and a misleading impression, he defined the latter as being economical with the truth.
Sometimes, it may be better to tell a lie than to tell the truth, especially if the truth will hurt or offend the listener more than a lie would. Such ‘good’ lies are known as white lies. Telling a pack of lies (one lie after another) is another matter, however, as in ‘The defendant was accused of telling a pack of lies to save his own skin’.
If a lie is particularly blatant or obvious, we can say that someone is lying through their teeth, as in ‘They say they’re not married but they’re lying through their teeth’. If you need to correct yourself because you realise that something you have just said is not correct, you can use the expression I tell a lie, as in ‘There were only five people at the meeting … I tell a lie … there were six’.
Sometimes, of course, the truth hurts (is unpleasant or upsetting to hear) and occasionally it may be necessary to emphasise that something is not true. In this situation, the expression nothing could be further from the truth can be used, as in ‘I don’t hate you! Nothing could be further from the truth'.
Finally, in a number of situations the time arrives when you will find out if something has succeeded or happened: ‘The moment of truth has finally arrived when the 32 teams competing in next year’s World Cup will find out who they will play against’.