What does Paul mean by another gospel in Galatians?

Paul's mention of 'another gospel' in Galatians 1:6-9 refers to any teaching that deviates from the core truth of the gospel of grace. He emphasizes that even if an angel from heaven were to preach a different message, such a person should be accursed, highlighting the seriousness of distorting the gospel. This 'another gospel' often involves adding works to the grace of God or altering the sufficiency of Christ's sacrifice. Paul is adamant that the authentic gospel is one of grace alone, through faith alone, in Christ alone, and any deviation from it threatens the very essence of the Christian faith.