Just what is the “Gospel of Jesus Christ Himself”, if you don’t mind my asking.
I find that if you ask this of a RC, you will get, "Keep the sacraments, trust Christ (as evidenced by keeping the sacraments), and keep the sacraments." Did I mention, "Keep the sacraments"? Also, pray to Mary, believe in papal inerrancy ex cathedra, do penance, get ready for pergatory, pay indulgences (making a comeback), and try to be holy.
If you ask a person who has read the entire Bible, they will tell you that the Gospel of Jesus is the good news that He has elected some before the foundation of the world to trust Him, and Him alone, for their rescue. He has adopted them, forgiven them, clothed them in His righteousness (not their own), and is sanctifying them until the day of their final redemption. They are safe in His hands, filled with His Spirit, still failing as humans but looking to Him for righteousness, not themselves. Notice how much He does versus they do? Jesus does for us what we cannot do for ourselves.