What does the Bible say about the one true gospel?

The Apostle Paul declares in Galatians 1:6-9 that there is only one true gospel, revealed through Christ. He emphasizes that any gospel contrary to the one he preached is a perversion and must be rejected. Paul marvels at the Galatians for so quickly turning from the gospel of grace to a distorted version that adds works to faith. This underscores the centrality of grace in the gospel, as any addition to it voids the grace of God, making salvation dependent on human actions rather than divine grace.