He gave the analogy of going into a very dusty, dark attic with a flash light. And he goes on to say that when you turn the flash light on, you don't say "Oh no, look at how much dust my flash light has caused!" Why? Because the light is only revealing what is already there. Grace is that light. Law just covers things up and never really deals with it. Grace brings it out into the open.
I've noticed since coming to grace, my sin is much more obvious. I've lost my temper even worse than I would when I was living under law. But thats not to say grace caused me to sin. It's only revealing whats already in me. And only by realizing how sinful I am, can I come to Christ, rather than the law to give me change in my life.
Grace doesn't cause you to sin. It only reveals whats already there. It doesn't increase sin. I know this sounds scary, but it's true. If you see that you have started sinning more obviously under grace than under law, then don't be afraid. You're not getting worse, you're getting a revelation of your indwelling sin, which drives you to seek the Physician. Just go to Christ and ask Him for His Spirit to change you from the inside. Being under law and shoulds is simply muzzling sin, rather than dealing with it.
This is a quote from Rob,
"People say "If you take the law off me then I can just go out and commit adultery."
They are not getting the revelation of the message of grace.
They are getting a revelation of the adultery that is in their hearts."