What is the Gospel?

"The Gospel is not what makes you feel good, or for that matter, the Gospel is not even what works for you - because there are all kinds of human things that will work for you, if you're thinking in a humanistic way. But the Gospel in a sense isn't you at all, but it is what God did in Jesus Christ 2000 years ago, when he died for your sin. Now, it has bearing on you, but that's the truth, and we have to begin to proclaim that." - Dr. James M. Boice.