Teachers who say that works are unimportant are spreading lies—by confusing the issues, by blunting the incentive to keep the commandments of God and to make the right kind of choices, by making people think that they do not have to do any works. Understand, however, that works are not required to save us but to ensure that we are changed!
What does God want to see when we come before the judgment bar, as we are now during our Christian lives? He wants to see evidence to prove that we are indeed His children. His judgment is based upon what we have done; the Bible says repeatedly that judgment is according to our works.
I am not qualifying here the quantity or the quality of our works. God is so merciful! Paul tells us in I Corinthians 3:15 that, even though our works are burned up, we ourselves will be saved. Even though the works are of poor quality, at least we have worked! We did not just sit there, dead in the water. We apparently pleased God enough to show that we wanted to be in His Kingdom.
That judgment is in His hands. But we should recognize that He does require works. The works are not for justification but for sanctification. The works aid in the transformation of our character to the image of God. The works aid in our growing in the grace and knowledge of Jesus Christ. The works help to produce change. It is a cooperative effort that we do with God.
And I can guarantee you that, if a person does not make the efforts to change, he would be totally unhappy in the Kingdom of God. He would be like a fish out of water, because everybody in that Kingdom is going to be holy. Everybody in that Kingdom is going to do—they are going to live holy lives. (An unholy person wouldn't fit, and so he won't be there.)
Satan is trying to destroy God's purpose by subtly confusing the necessity of good works, and therefore stopping the process of sanctification through a perverted teaching on grace, law, and covenants. But remember this: Hebrews 12:14 tells us that without holiness—a holiness that we have to strive for—"no man shall see the Lord."