I will make this very short. Read the writings of the apostolos. “Testimony of two or more confirm the fact.”
Luke 24:25-27, 45-46 1 Corinthians 15:1-6
The gospel Paul preached is Yeshua’s gospel. There are not many gospels. There is one gospel. This matter is settled in the grace of God.
There is no disagreement in the grace of God concerning the one true gospel. If there is disagreement, it is by the father of disagreements, of lies. If there are disagreements, it is by the “diabolos”, the false accuser, the devil, who speaks out of lying spirit, that God has more than one gospel. He falsely accuses God. Let God be true and every man a liar. There is one and only gospel. This is as sure and true as there is only one mediator between God and man, the man, the Christ, Yeshua.
They who have ears to ear (by the grace and will of God), hear what the Spirit says to the assemblies.