One of the gifts Lutheran theology has given the Church at large is the distinction between Law and Gospel in the Holy Scriptures. Law is about COMMAND. It reveals who God is, and what God considers to be right, true and good. As such, the Law is holy. But in its commanding, it accuses. After the Fall, the Law, instead of acting as a guide, started demonstrating we couldn't live up to God's standards. It follows that the Law cannot give salvation. What the Law does so effectively however is to shut us up - we see the reality of who we are, and the huge gap between what we are and what we do and that which God requires of us. The Law in its commands finds us guilty, and there is nothing we can do to get out of the mess we have found ourselves in before a holy and righteous God. The solution that God comes up with in his steadfast love is the Gospel, which is all about PROMISE. The Law tells us what we should do; the Gospel tells us what God has done. The righteousness, which the Law in its commands shows us that we need, is found in a source outside of ourselves - in God himself, in his free grace. The gospel is good news - a great good rejoicing announcement of all that God has done for us in the saving life, death, resurrection, ascension and intercession of Christ. How astonishing is the gift of Christ's righteousness to cover our lawlessness! And how kind that Christ himself, by his Spirit, comes to live within us, so that from within we have the power and the ability to do what we could not do before - we keep God's commandments, and these same commands become descriptions of what the Spirit is doing within us.
Very well then ... but there is a battle going on, a battle with the enemy of our souls. And it struck me recently that Satan twists Law and Gospel in his attacks on us. Satan applies the Law to our past, and reminds us of how far we have fallen; and how wretched we are; and how much we let the Lord down. Then in his malevolence he twists the Gospel and applies it to our future by sneakily suggesting it doesn't matter how we live, 'God will forgive us.' But this is horribly wrong, demonically back to front.
It is to our past that the Lord in his grace applies the Gospel: all our sins are forgiven and are remembered no more, covered by the precious blood of Christ. That's how we defeat Satan's accusations -"by the blood of the Lamb" (Revelation 12:11) And then it is to our futures that God applies the Law - commanding us to live in ways that please him. And only then, can we say that his commands are not burdensome, because we have the Spirit living in us, causing us, in the fear of his name, to love what he loves, to hate what he hates, and to do what he wants done.