How is it not different?How is Paul's message different?
I invite you to answer the questions I just posed to LA.
They illustrate just two of the differences between Paul and the twelve but to give you a direct answer, the difference is the Gospel of Grace.
No one other than Paul preached the gospel of grace - no one. Not Jesus, not Peter nor James nor John nor anyone else.
Romans 4:5 But to him who does not work but believes on Him who justifies the ungodly, his faith is accounted for righteousness,
That idea is exclusive to Paul!
Further, there are lots and lots of doctrinal debates in the church that have persisted for centuries and a great many of them, if not all of them, fall along the lines of Paul vs Peter, James & John.
Is water baptism required for salvation?
If you say, "Yes", you'll cite the New Testament books NOT written by Paul, including the Gospels.
If you say, "No", you'll cite nothing at all but the books written by Paul.
The same is true about whether works are required for salvation, or whether you can lost your salvation, or speaking in tongues, or whether the rapture will occur before or after the Tribulation, or whether you should only eat certain kinds of foods, or whether you should observe the Sabbath or tithe or obey the Ten Commandments, etc, etc.
All of these seemingly unrelated issues, and many more, all fall along the lines of Paul vs the rest of the Biblical authors and so I'm not being flippant at all when I say that the list of what isn't different is much shorter than the list of things which are different. Very nearly the whole thing is different because the difference is literally the difference between observance of the law being required vs. observance of the law being prohibited.
Resting in Him,
P.S. Here's an excellent example of just the sort of doctrinal debate I'm talking about. Skim through the first several posts and take note of the proof texts on each side...
Swine Sausage - Sin?