What is the difference between legalism and the gospel?

• Legalism (or Moralism) says God looks at how well we keep the law.
• The Gospel says we are hidden in Christ. So God sees how well Jesus kept the Law (perfectly), all his works, and his death on our behalf.  Consequently, because we are hidden in Christ, God sees the work of Jesus when he sees us. The gospel says that, because of God’s grace, all that Jesus is and did is credited (imputed) to us, through faith.  (Colossians 3.3, Ephesians 2.8, Romans 5.2, Galatians 2.20)

So what is the difference between the gospel and legalism? It is the difference between Christianity and every religion in the world.