C.f.w. Walther said this quote

Every religion contains portions of the law. In fact, some unbelievers, by their knowledge of the law, have advanced so far that they realize that their souls need to be cleansed, that their thoughts and desires need to be purified. But only in the Christian religion will you find the Gospel. Other religions do not contain even a speck of it.

~ C.f.w. Walther

...according to God's Word, we should not give a singe drop of evangelical consolation to those who are still living in sin. ON THE OTHER HAND, we should not address the slightest threat or rebuke to the broken hearted--but only promises delivering consolation and grace, forgiveness of sin and righteousness. Life and salvation.

~ C.f.w. Walther

The main thing to tell a person when you explain how to become righteous is to announce to him for free grace of God, concealing nothing, saying none other than what God says in the Gospel. Build a fence around Mount Sinai, but not around Golgotha ,because at Golgotha all God's wrath was appeased.

~ C.f.w. Walther

Here is where most preachers make their mistake. They are afraid that by preaching the gospel too clearly, it will be their fault if people lapse into sin. They imagine that the gospel is food for the carnal-minded. True enough, to many the gospel does become the smell of death unto death, but that is not the fault of the Gospel. That happens only because men do not accept -do not believe-the Gospel. Faith is not merely thinking, I believe. Your whole heart must be seized by the gospel and come to rest in it. When that happens, you are transformed and cannot help but love and serve God.

~ C.f.w. Walther