Now I would remind you, brothers, of the gospel I preached to you, which you received, in which you stand, and by which you are being saved, if you hold fast to the word I preached to you—unless you believed in vain.
For I delivered to you as of first importance what I also received: that Christ died for our sins in accordance with the Scriptures, that he was buried, that he was raised on the third day in accordance with the Scriptures, and that he appeared to Cephas, then to the twelve. Then he appeared to more than five hundred brothers at one time, most of whom are still alive, though some have fallen asleep. Then he appeared to James, then to all the apostles. Last of all, as to one untimely born, he appeared also to me. For I am the least of the apostles, unworthy to be called an apostle, because I persecuted the church of God. But by the grace of God I am what I am, and his grace toward me was not in vain. On the contrary, I worked harder than any of them, though it was not I, but the grace of God that is with me. Whether then it was I or they, so we preach and so you believed.
(1 Corinthians 15:1-11 ESV)
The Apostle Paul has tough words for a wayward church. The thing about the church in Corinth was that they had not totally forsaken Jesus, but they were in danger of a kind of spiritual pride that tends in the same direction. That’s why Paul needed to remind them of the most basic things elements of the gospel. When he says, “unless you believed in vain,” he is talking about people who “believe,” but because what they believe is, to them, on the level of superstition or fantasy, it has no real effect. You don’t worship Indiana Jones because, even though you may believe in him, he is not real, nor can he speak with you personally. All of the words of Indiana Jones are on film and will never be altered.
This will probably sound redundant, but in an age where fantasy and reality seem to overlap so often on TV, what Paul is saying is that Jesus actually died for or because of our sins; and that was prophesied beginning some 2000 years before he appeared. He was actually buried. That is he actually died. That is an actual, real death of the body. After that he actually became alive again. That is, the very real human body he had lived in for 30 years actually came to life once more after enduring the most vicious attacks and violations. And just to be sure we don’t mistake this event for something else, it took a period of three consecutive days while his body was cooling off and rigor was setting in before he was alive again, and by his own testimony, he chose to become alive again of his own will. And all of THAT also happened according to words that were spoken a very, very long time before Jesus was even born.
Why is this all impotant? Because the good news Paul preached to the believers at Corinth was news of a personal meeting Paul had with Jesus after his resurrection and ascension. Paul didn’t have some kind of “spiritual” encounter with Jesus (ie. Where you “feel like God spoke to you”). Paul had a real discussion with Jesus on several occasions. All of this is important because Paul delivered it to the Corinthian believers because it was “of first importance.”
Paul preached a real Jesus, the Corinthians received a real Jesus; they were standing with a real Jesus and they were being saved by a real Jesus who actually saves people today the same way he saved Paul. We are saved by his gift, freely given. We are loved with an eternal love.