The LORD bless you and keep you; the LORD make his face to
shine upon you and be gracious to you; the LORD
lift up his countenance upon you
and give you peace.
Numbers 6:24-26 ESV
At the conclusion of his last sermon, three days before his end, he took formal leave of his dear friends in Eisleben with the words: “Now after I have been here for quite a long period of time and have preached to you and now must depart and might preach no longer, so I want to bless you by this, and I have prayed that you would strive to remain with the Word, that your preachers and pastors would faithfully teach of God’s grace, and I commend you to pray that God would defend you against all the wise people and all people who despise the doctrine of the Gospel, for they have often caused great harm and still might.”
Luther stresses the "paradox" (contraria) by stating that the verdict of law and gospel are absolutely contradictory (contradictoria). He says, "These two things are diametrically opposed [ipsa ex diametro pugnant]: that a Christian is righteous and beloved by God, and yet he is a sinner at the same time. For God cannot deny His own nature. That is, He cannot avoid hating sin and sinners; and He does so by necessity, for otherwise He would be unjust and would love sin. Then how can these two contradictory things both be true at the same time, that I am a sinner and deserve divine wrath and hatred and that the Father loves me? Here nothing can intervene except Christ the Mediator." This last simple sentence explains the paradox. It explains the whole Christian religion. It explains the Scriptures. It is the secret to all exegesis of Scripture and all theologizing. It is the only comfort that a poor sinner has in life and in death. It is "Christ alone." So we have in the principle of solus Christus not only a hermeneutical rule, not only the basis for all comfort, not only the basis for our union with God and for reconciliation and salvation, but the principle of all human knowledge and understanding.