Can you identify the elements of Paul's definition of the Gospel? First of all, Paul states that it's something which they "received" and were "saved." He adds that Jesus was "buried" and that He was "raised on the third day." Do you notice anything else significant about his definition? Notice that Paul adds that his Gospel message to the formerly lost Corinthians had included mentioning that "Christ died for our sins." "Oh," but the Calvinist says, "Paul is speaking to Christians." But regardless of who he is speaking to, Paul is defining what the Gospel comprised, back when he had spoken it to them when they were lost. And notice that Paul didn't say, "Christ died for sin." Of course, Jesus did die for sin. But Paul makes it personal.
Unless there are many Gospels, which no Calvinist espouses, Paul defined what the ONE Gospel included, which is the fact that "Christ died for our sins." Now that doesn't mean, "just my sin." To be clear, "our sins" means your sins and mine, speaker + audience. That's the impact of "our." It is a mutual inclusion. I'm trying to make this as plain as possible. Paul's Gospel obliterates Limited Atonement. Paul told lost people that Jesus died for them. Paul recalls that this was the Gospel when he had preached to them.
One Calvinist responds: "First Corinthians was written by a Christian, namely Paul, to Christians. So Christ died for 'OUR' sins means 'OUR.' Not theirs, don't add to the gospel."
"Our sins" is inclusive. It means your sins and mine. The speaker includes himself together with the lost audience that he had preached the Gospel to, and who received it and were saved. Is this really Calculus? Is this really hard to understand? Or is the problem, not necessary a factor of intelligence, but of cultic indoctrination, which refuses to see the light? You could tell a cultist that 1+1=2, but they will try to argue that it somehow really means 1.5 or 3. It's like you cannot make it simple or plain enough, and that's because logic and reason are not the problem. A culticly indoctrinated person can reconcile anything, such as spinning John 3:16 to mean, "For God so loved the world of the elect." For that person, no amount of logic will work. Their mind is shot. They cannot engage in reason. They will only engage in spin and obfuscation.