Had it not been for Christ, Paul would have had no message to preach. We either believe Paul’s claim to be an apostle of Christ or we reject it. Now I accept his claim to be a genuine apostle, even though he is the only disbeliever to whom the risen Lord Jesus revealed himself. The word is that he was a chosen vessel. It is important to realise that as an apostle of the Messiah, or as Paul claimed at one time and ambassador of the Lord, he was not preaching his own ideas, as you suggest, but the word of Christ.
The Lord Jesus commissioned his apostles to make disciples of all nations. Now the biggest problem is not logistical but cultural – getting the message across. The risen Christ was proof that Jesus was the Messiah, but once you move out of Jewish circles that message has no impact. However, that Jesus is Saviour, and Jesus is the ultimate Judge, does. The gospel is preached so that a person can be saved. There are many people who pick the bones of the niceties of theology to enhance their intellectual status with no view of becoming right with God.
Anyway it is the apostles’ teaching the Church follows. You may well say that such and such is Pauline and that is Johine, and yes we can recognise certain individual characteristics, but unless we are prepared to acknowledge that the teachings are ultimately from God – what are we doing – some form of religious pick and choose?
So what is the basic message of the gospel. Stop doing things your way and have faith in God.
Paul was able to say what God had done. What has been achieved through Christ.
We like the idea of blessing, we don’t like the idea of damnation, and we have a tendency to say, ‘We will believe in you, God, if we can do things our way.’ Believing is easy. Repentance and fully trusting God for many of us is just a step too far.
When Saul of Tarsus, (later known as Paul) he persecuting those of the way (later to be known as Christians) he was doing as far as he was aware, the work of God. We like to do the work of God especially if it is self determined. Relying on God to do His work is an alien concept to our minds, and many of us are prepared to do anything and everything apart from what God actually asks us to do.
Basically God gave Christ (His anointed one) work to do, which he fulfilled. Christ gave his apostles work to do, which they carried out and which the Church will continue until Christ returns.