The careful student of the Epistles of Paul soon observes that the Apostle makes many specific statements as to the distinctiveness of his ministry and message. Even apart from this, however, and considering his phraseology alone, we often wonder how anyone could possibly deny that his message was distinct from that which the twelve had proclaimed. Note the following examples:
Rom. 2:16: “In the day when God shall judge the secrets of men by Jesus Christ, according to MY GOSPEL.”
Rom. 16:25: “Now to Him that is of power to stablish you according to MY GOSPEL, and the preaching of Jesus Christ according to the revelation of the mystery, which was kept secret since the world began.”
II Tim. 2:7,8; “Consider what I say; and the Lord give thee understanding in all things.
“Remember that Jesus Christ, of the seed of David, was raised from the dead according to MY GOSPEL.”
Gal. 1:11: “But I certify you, brethren, that THE GOSPEL WHICH WAS PREACHED OF ME is not after man.”
I Cor. 15:1: “Moreover, brethren, I declare unto you THE GOSPEL WHICH I PREACHED UNTO YOU, which also ye have received, and wherein ye stand.”
Add to this the Apostle’s explicit claims as to the distinctive character of his ministry and message and you have irrefutable proof of the fact. source