Did you know that observance of the Law has nothing to do with justification? This comes as a shock to many people, but the truth is, that the Bible says, man is justified and made upright by faith independent of and distinctly apart from good deeds. In other words, there is nothing that you can do to ever earn your salvation.
A friend of mine was telling me a story about one of his employees who was searching for the truth and as they were talking, the employee recited a long lineage of the things he had done to earn his salvation. My friend said something to him that has stuck with me. He told him that salvation was a lot simpler than he was making it out to be. It wasn't what he did to earn it, it was what Jesus did to provide it.
Why do we make it so hard? Why do we complicate the simple truth of God's Word? Why do we want to add to what Jesus already did for us? Paul told the Philippian jailer in Acts 16:31, "Believe in the Lord Jesus, and you will be saved..." Believing is all it takes, but believing takes faith. Faith and faith alone is what is required of us. So in that sense, my friend was completely right... it [salvation] is a lot simpler than measuring up to the standards of the Law.
Paul's main point here, is that God did what we could not do. When we put our faith in Him, then and only then are we justified before God. It has nothing to do with the Law. We were never able to fulfill it or even come close to it. Therefore, the Law pointed out in us, the need for a savior. When we abandon the things we do as the means of salvation and turn and put our faith in Jesus for salvation then we are justified by Him. What great news this is!