From the pen of the sainted Martin Luther:
Jesus is the greatest of sinners. There is no greater sinner in the entire human race than the Son of God. This is so true that He is called sin itself (God made Him who knew no sin to be sin for us, so that in Him we might become the righteousness of God. 2 Cor. 5:21).
His sin is ours. It was foreign to Him. He had none. He committed none. It was made His own because of the love wherewith He loved us. He bore it, and because He suffered as though He had committed it Himself, although He was entirely innocent and spotless. He was the Lamb foreseen from the beginning of the world, the woman's Seed promised to our first parents, Adam and Eve, immediately after their fall. (From "What Luther Says" page 1421).
Luther often described 2 Corinthians 5:21 with these words, "The Joyous Exchange." While we can imagine the pain and suffering Christ endured on the cross to be joyful in any way at all, still, the writer to the Hebrews put it like this: Jesus...who for the joy set before Him endured the cross, scorning it's shame. (chapter 12:2).
And becoming "sin for us" we received in exchange the righteousness of Jesus. This "glorious dress" (see verse one of the hymn, "Jesus, Thy Blood and Righteousness") makes us acceptable before our Heavenly Father. In many ways, it is a one-sided exchange. Jesus receives our punishment for the sins we commit; we receive the perfect holiness and righteousness of Jesus which we need but do not deserve. God's grace is truly amazing! Now you know what Luther called it "The Joyous Exchange."
