The Pharisees believed that a person was declared by God to be righteous based on his obedience to the Commandments, and they didn’t believe they were sinners in need of repentance because of their often sincere zeal in obeying those Commandments.
Christianity remains infected with the Pharisees’ attitude, especially the first part. Many think that they can or must do something to earn forgiveness and eternal life. The flagrant manifestation of this error occurs when Christ is represented as a new Moses or lawgiver, and the gospel is turned into a doctrine of meritorious works (Walther's Law and Gospel, Thesis 5). This error is further compounded with the theory that Matthew’s Gospel actually portrays Jesus as a new Moses.
I was actually taught in college that Matthew's Gospel portrays Jesus as a new Moses. I really didn't give it much thought back then in the late '80s and early '90s. However, over the years, I realize how that teaching can completely undo the gospel that we are saved on account of Christ alone. Matthew does not teach Jesus as a new Moses who gives us new laws -- to do so would smack of Pharisee-ism, and the temptation to fall into the pharisaical error would be too great.
Matthew's Gospel focuses on the suffering, death, and resurrection of Jesus who saves us from sin, death, and the devil. "If we did not know Jesus' death, we would not know Jesus. Any account of Jesus that does not collapse with the removal of the passion is not an account of Jesus" (Selected Sermons of Norman Nagel, 77).
But how does this square with Christianity today? How many churches teach a passionless Christ, or merely give it lip service, in their quest to preach something else. It's easy to point out how the televangelists preach a Christless and a Crossless Christianity, but how about our own Lutheran churches?
The gospel is such a precious jewel, and we must ensure that it is preached properly and purely. Pastors must be vigilant in holding the bright light of the gospel of Christ crucified front and center before the churches and the people. We are not redeemed by obeying the Ten Commandments, not even a little bit. We are so corrupt inside and out; even one single sin condemns us to hell, let alone the fact that we are born sinful; we can't do anything about that. From the moment we are born we are sinners who deserve hell.
The gospel tells us that we are redeemed by Christ alone who goes to the cross alone. Salvation is not our doing, but Christ's. His merit is given to us as a free gift. We don't have to do anything to earn this gift (because then it would cease to be a gift). We don't have to do anything pay for this gift.
Chrisianity has a great gift, the only gift, to share with the world. If you want to know what to do, how to live your life, then look to Moses and the Old Testament. If you want to know how to obtain eternal life and the forgiveness of sins, then look to Christ alone. He is our Savior; He did it all for us; He gives us salvation freely. He is the only means of obtaining salvation.