This is from the Thirsty Theologian...
This might be the most shocking statement you read all day: The death of Christ was not enough to save us. Now, before you write me off as a heretic, read what RC Sproul has to say about it.
"If Jesus had only paid for our sins, He would have succeeded only in taking us back to square one. We would no longer be guilty, but we still would have absolutely no righteousness to bring before God. So, our Redeemer needed not only to die, but also to live a life of perfect obedience. The righteousness that He manifested could then be transferred to all who put their trust in Him. Just as my sin is transferred to Him
—RC Sproul, The Work of Christ (David C. Cook, 2012), 8.