Bible doesn't think for you, being allegory & mystery: allegoric mystery; Rather purposed to make you think?

He is telling the people that you can't live by the law. It won't get you to heaven, but at the same time the law is good because you know you fall short. Jesus fullfilled the cerimonial law. He didn't touch the moral law. So only by grace and being filled with the Holy Ghost will save you. The Holy Ghost enables you to stay away from sin. But if you do sin, we have an adovacate with the father. And thru grace we might find forgiveness.