There is no such thing as "Paul's Gospel" versus…

There is no such thing as "Paul's Gospel" versus a separate gospel in Matthew through John. The Bible does not have multiple, divided gospels. There is only ONE eternal Gospel, and it belongs entirely to Jesus Christ.
Here is what Scripture actually says to clear up the confusion in this post:
1. The Gospel Existed Long Before Paul (Abraham Heard It First)
The graphic in the post claims that "Paul's Gospel" is a completely separate mystery found only from Romans to Philemon. However, Scripture explicitly states that the exact same Gospel was preached to Abraham thousands of years prior:
* Galatians 3:8: "And the scripture, foreseeing that God would justify the heathen through faith, preached before the gospel unto Abraham, saying, In thee shall all nations be blessed."
2. The Word of God is Not Divided (There is Only One Gospel)
God's word is not split into different plans of salvation for different eras. Paul himself fiercely condemned the idea that there is more than one gospel:
* Galatians 1:8: "But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed."
* 1 Corinthians 15:11: Speaking of the other apostles who walked with Jesus, Paul wrote, "Therefore whether it were I or they, so we preach, and so ye believed." They preached the exact same message.
3. "Endure to the End" is Not "Satan's Game Plan"
The graphic claims that enduring to the end, repenting, and keeping God's ways is "religion, not the gospel." But Jesus Himself commands us to endure. Enduring to the end simply means to continue to believe, remain in His love, and not wander off the narrow path.
* Matthew 24:13: "But he that shall endure unto the end, the same shall be saved."
* Hebrews 3:14: "For we are made partakers of Christ, if we hold the beginning of our confidence stedfast unto the end."
When Paul used the phrase "my gospel" in the verses you quoted earlier, he used "my" the same way a royal messenger says "my message." It didn't mean he authored a separate doctrine; it meant he was personally entrusted to proclaim the one and only Gospel of Jesus Christ to the world.