Just because you've seen it done on TV doesnt necessarily mean you can do it yourself. Its true, there are a lot of skills a person can learn by reading a book or watching someone else, like basic plumbing or landscaping. However, there are other things that are always best left to the professionals.
Thats why they dont sell Do it Yoursel Appendectomy kits at the drug store. That would be dangerous and downright silly. Just as pointless are the attempts we make to cure ourselves from sin. We may hope to overcome sin by being more disciplined or by reading self-help books. Those aren't bad ideas, its just that any attempt to overcome sin on our own will fail. Why? Because no matter how disciplined you become, or how many times you got to church or read your Bible, those things, in themselves, are not the cure. Just as we need to go to a surgeon to remove an infected appendicts, so we need God to remove our sin. It cant be done on our own. In fact, any individual attempt to cure sin by our own effort is simply another sin! Its the sin of pride.
To have your sins completely removed, we must go to the Great Physician. He will get it done right the first time no matter how many times you've tried on your own.