What you do if someone lied?

I'll ignore him next time ,and I wont belive his words any more.

UI will tell him that lying is the brother of stealing. i will not be mad at him ill just tell him that he need to correct the attitude because it will be his habit . Ill pray for him and ill be helping him to change the attitude

Lying is no big deal. We lie all the time. I would do nothing immediately, because I can judge truths from non truths-I would simply let him go on with his lies until it is all done. The good thing abut lies is that it easily catches up with liars over time. When a lie is exposed bare by certain contradictions, the best thing you can now do is try to remind the liar what he/she once said on the same topic, there you make him look like a little wingless insect!