It isn’t meaningless at all. You claim that the Gospel originated with the Roman Catholic church, but the truth is, it’s found all through out the OT, very clearly in the book of Isaiah.
That’s why it’s’ so much fun to share the Gospel with Jews. They’re absolutely shocked when you show them these things from their own scriptures.
In fact, take the time to read Isaiah 53:5-6,10-11 sometime.
Using the language of the Old Testament sacrificial system, Isaiah says this Person will lay down his righteous life as an atoning sacrifice for Israel’s sins.
This confirms what the sacrificial system implied, that God’s ultimate atonement would require the voluntary death of a unique Person, not animals.
Because he is God’s perfect sacrifice, his death will purchase full forgiveness of sins. Therefore, it will not have to be repeated over and over again like the animal sacrifices. (In fact, it puts them out of business altogether.)
And His death will provide not only for Israel’s forgiveness, but also for the rest of the world. Read Isa. 52:15.
This reads so much like a “Cliff Notes” of the Christian gospel that many skeptics charged that it was a Christian forgery inserted back into the Old Testament.