What is the Gospel?

We can never stray from the central point of everything...

You and I are sinners.  We have all fallen short of the glory of God.  We do not measure up to the holiness God requires.  Not us in our worst, but we at our best are still not righteous enough for the favor and justification of God Almighty.  So God in Christ makes a way.  He imputes to us the righteousness of Christ.  Your righteousness is inadequate, so if you could check off all those things on your box of what Christians do, the Bible still says your righteous deeds are as filthy rags to Him.  So we're going to need a righteousness that goes well beyond our own
righteousness, and we get that in Jesus Christ.

Jesus gives to us His perfection. He gives to us His righteousness. Then on top of that, on the cross of Christ Jesus takes from us the wrath of God due us for our rebellion against Him. So you have imputed righteousness, wrath-absorbing death, and in the resurrection we see the great exchange is complete.  Here is the most spectacular part of it all: You didn't do anything to get that. So God saved you. God rescued you. God opened up your heart. God revealed this to you. You played no part in your salvation except glad submission.

http://theresurgence.com/2012/08/14/why-the-gospel-is-offensive

"The gospel is not that Jesus Christ comes to earth, tells us how to live, we live a good life, and then God owes us blessing. The gospel is that Jesus Christ came to earth, lived the life we should have lived and died the death we should have died." - Tim Keller