Luther didn't get it all right
"The Destruction of the European Jews" by Paul Hilberg is a solemn reminder of how potent words are. Martin Luther, the reformer, wrote a book, "About the Jews and Their Lies" which expressed and repeated views about the Jews (common in his time) which contributed to a bad attitude towards Jews in German culture leading into the second world war.
Basically, Luther says that Jews want to rule the world, they are archcrimnal killers of Christ - and all Christendom, and frankly they are a plague. Not a very Christ-like attitude, you will agree.
Perhaps Luther's view of the Jews shocks you, it shouldn't: only One Man is worthy of our devotion. I am not in the least surprised that Martin Luther was plain wrong on the Jews, as well as on subject B, C, D (there are probably not enough letters in the alphabet).....
On Justification by faith he got it right
And yet Martin Luther remains an important figure in the story of the church because he insisted (or re-insisted, shall we say) on the radical and wonderful message of the Gospel, which in summary form is about a God who justifies the wicked (Romans 4:5). We are not saved by our works, we are saved by mere faith in Christ, plus nothing. And even that faith comes form God (Ephesians 2:8-9), so we are saved by God from first to last; we contribute nothing to our salvation (except perhaps our sins).
This glorious Gospel gives hope to the worst of sinners: they can come into his glorious kingdom by faith in Christ. And it gives hope to failing believers; their 'performance' does not affect their standing with God - he still loves them and they are still dressed in the robes of his righteousness. This is in part what motivates a believer in the great task of sanctification - they are amazed at the eternal unchanging steadfast love and grace of God to sinners and want to respond in loving obedience.
Simul Iustus et Peccator
Simultaneously Justified and a Sinner
In this life I am always a sinner, but by the grace of God, at the same time, by faith in Christ I am a justified sinner.