If you’re good inside, you’ll do good things. If you’re bad inside, you’ll do bad things. And what you say will give you away, one way or the other, every time.
Sure, you can fool some of the people some of the time. But it won’t take long for people to figure you out. They may not say anything, but they know.
Chances are, the only person you’re really fooling by trying to say something different than what you’re really thinking is yourself.
Best practice: tell the truth. And if the truth is ugly, don’t bother with band-aids. The only real fix is to fix the you that’s on the inside.