Paul summed up the Gospel like this:
“For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, that he was buried, that he was raised on the third day according to the Scriptures, and that he appeared to Cephas, and then to the Twelve. After that, he appeared to more than five hundred of the brothers and sisters at the same time, most of whom are still living, though some have fallen asleep. Then he appeared to James, then to all the apostles, and last of all he appeared to me also, as to one abnormally born.”(1 Corinthians 15:3-8).
As you can see, Paul thinks that at the core of the Gospel lies Jesus’ death for our sins, His burial and His resurrection. And among these three, the resurrection receives most attention. He lines up everyone he knows of that has seen the resurrected Jesus, including himself. Then he goes on discussing the resurrection in the rest of the chapter.
Likewise, Paul, Peter and others who preach the Gospel in the book of Acts often emphasize the resurrection even more than they emphasize the cross. This used to confuse me, since the atonement happened on the cross. It was on the cross that Jesus died for our sins and defeated the devil – the cross is at the core of all atonement theories. The resurrection is great of course, Jesus is alive hallelujah, but shouldn’t the death of Jesus be the focus of the apostles rather than His resurrection?