Not every gospel is the true gospel. The New Testament believers in Galatia were drawn away from the gospel they originally received from Paul to “a different gospel” (Gal. 1:6). This “new” message was marked by an absence of God’s grace. Proclaimed by those who believed that converts to Christ who did not come from a Jewish background ought to be circumcised and abide by the regulations of the Mosaic law, it made salvation a matter of human effort, something to be earned by those who relied upon their own good works.
Paul rightly characterizes this change to his message as a perversion (Gal. 1:7). In his criticism of the Galatians, the apostle identified three distinguishing marks of the true gospel: grace, faith, and a focus on the person of Jesus Christ. The biblical gospel is a message about grace. It is the promise of a righteousness that comes from God and can only be received as a gift through faith (Gal. 2:15–16). But it is also a message about Jesus Christ. The righteousness offered to those who believe the gospel is Christ’s own, purchased for them by His obedience, death, and bodily resurrection. The true gospel is a call to personal faith in Jesus Christ (Gal. 3:26).
The gospel is also a message of power. Those who believe are given the capacity to “live by the Spirit” (Gal. 5:16). They gain ability to resist the passions and desires of the sinful nature. The false gospel and the true gospel are both concerned about moral behavior. But in the true gospel, moral behavior is a fruit of God’s own work in the believer. There is still human effort involved but it is divinely empowered effort. In the false gospel, obedience to God’s commands is an attempt to earn His favor. In the true gospel obedience is an expression of gratitude for a forgiveness already received and a righteousness already obtained.
It makes no difference if those who preach a different gospel are as impressive as an angel from heaven. God’s judgment of their “ministry” and message is clear. Any gospel that differs from the gospel Paul preached is really no gospel at all (Gal. 1:7).
FOR FURTHER READING
To learn more about Paul's explanation of the true gospel, read Martin Luther's commentary on the book of Galatians in the Crossway Classic Commentaries series (Crossway).