There is only one gospel that can save mankind from their sin, the gospel of grace. It is best defined in 1 Corinthians 15:1-4.
The apostle Paul didn’t proclaim to the idol-worshiping pagan Gentiles at Corinth “that they needed to accept Jesus into their hearts in order to be saved”. Nor did Paul tell those ungodly pagans to “confess that Jesus is Lord in order to be saved (even the demons know Jesus is Lord)”. No, he told them exactly what the risen and glorified Lord told him to preach.
To believe that Jesus Christ died for their sins was buried and rose again the third day and they would be saved.
And this is exactly what the apostle Paul wrote in 1 Corinthians 15:1-4.
‘Moreover, brethren, I declare to you the gospel which I preached to you, which also you received and in which you stand, by which also you are saved, if you hold fast that word which I preached to you—unless you believed in vain. For I delivered to you first of all that which I also received: that Christ died for our sins according to the Scriptures, and that He was buried, and that He rose again the third day according to the Scriptures, ‘
I Corinthians 15:1-4
All mankind will be judged at the great white throne by Paul’s gospel.
‘in the day when God will judge the secrets of men by Jesus Christ, according to my gospel.’
Salvation is by faith alone in the gospel alone in the finished work of the cross alone. Apart from the law and works (Romans 3:21).
‘But now (7-8 years after the cross and not before) the righteousness of God apart from the law is revealed, (up until the apostle comes on the scene this was not so) being witnessed by the Law and the Prophets, even the righteousness of God, through faith (believing) in Jesus Christ, to all(salvation is a free gift for ALL mankind not a special pick out group of people) and on all who believe (faith, trust, or believe all mean the same thing). For there is no difference (between Jew and Gentile); ‘
The gospel is simple and clear.
***yes, I know Jesus is Lord