For God’s Law is not a matter of pleasantry; it ceaselessly accuses consciences outside of Christ.

Apology of the Augsburg Confession,
Article III Of Love and the Fulfilling of the Law,
Triglotta 211. after par. 212 (not in the Latin)

One who does not constantly fear and act as if he were filled with mortal sins will hardly be saved at all.

Luther, Martin. Luther’s Works, American Edition, 1957. vol. 31, p. 242.

Comment: Understanding the context - the life of the Christian is not summarized by its fear, but its trust in Christ; but once a Christian loses sight of the depravity and seriousness of sin, and that even his best days are filled with 'mortal' sins (deserving of wrath and damnation), he will no longer appreciate the sacrifice of Christ and the necessity of the Holy Spirit's sanctifying work in his life. Pride and self-righteousness are a couple of the great destroyers of the faith (which hangs nowhere else but on Christ - not on oneself).

In differing degrees we all struggle with pet sins: anger, gossip, cursing, dishonesty, lustful fantasies, and more. When the failures in that struggle multiply, there’s a satanic lie that can push us into slavery: “I can’t help it.” Guilt intended by God to lead us to repentance is, instead, distorted into debilitating shame and self-hatred that make us feel even weaker in the face of temptation.

…The law nags us about our sins, and without Jesus’ forgiveness that nagging becomes preoccupation with our sins (cf. Romans 7:7-11). The law confronts us with the demand of perfection; but without the gospel’s assurance that Jesus’ righteousness is ours, that demand becomes the delusion that we must overcome sin ourselves (cf. Galatians 3:1-3). The law condemns us; and apart from the gospel’s proclamation that God has declared us not guilty, that condemnation will leave us defeated, weak, and helpless (cf. Romans 7:23,24).

Kelm, Paul E. Freedom from sin’s slavery, p. 29
October 2005. Forward in Christ – Series: Christian Freedom, Part 2, Vol. 92, No. 10

The seed of the gospel can germinate only in soil that has been tilled with the sharp blade of the law… To prepare the soil properly the plow must go down deep.

Kettner, Elmer. Concordia Theological Monthly, May 1953, p. 326
quoted by: Bivens, Forrest L.
Getting the Right Message Out – And Getting It Out the Right Way
Spring 2004. WLQ, Vol. 101, No. 2, p.116

As doctors at Children’s Hospital of Wisconsin discussed his condition, 11-year-old Ignacio Contreras understood what his mother, Margarita, could not.

…”He got so sad and I said, ‘Son, tell me what’s the matter. What are they saying?’ “ Margarita Contreras remembered.

“He said, ‘Mom, don’t cry. They say I have cancer.’ “

Pabst, Georgia. How to translate heartbreak
December 16, 2004. Milwaukee Journal Sentinel - Local

Comment: Like Paul says, the Law makes us conscious of our sin and its wages. Hopefully we can sense when someone has heard this sad diagnosis or feels guilty for their sins, and we can come with the cure - the cross of Christ.