Have you ever thought over this? Do you ever stop for a moment in life to think why everyone tell lies (here everyone implies God too)?
I don't understand why everyone keep telling lies. But I do understand that some lies are harmless and some helps in keeping the binding force in many a relationship intact and avoid unnecessary conflicts between confused souls. But serious lies should not be encouraged as they destroy "Trust".
About God lying as mentioned above (That I am going to prove though I am not an atheist), if one care to read the Old Testament, one can remember God himself told Adam and Eve not to eat the fruit from the Tree of Knowledge as they will get killed. Did they get killed after eating the fruit? So, obviously God was lying. What I am trying to convey here is not the fact that God lies too but the fact that the mental attitude of all is such that they lie once in a while....
But let's not make this habit of lying as serious lying and bullshitting. Because they destroy relationships and the believe/faith in others.....
The rest is your decision. Didn't anyone study Moral Science when they went to school?