What does it mean to stand firm in the gospel?

Standing in the gospel, as described in 1 Corinthians 15:2, signifies a firm commitment to the truth of Christ’s death and resurrection. It entails knowing that one's righteousness comes through faith in Christ alone and not through personal works. This firm standing is non-negotiable; believers are called to maintain their faith in the simple message: Christ crucified (1 Corinthians 1:23). It means persisting in that faith despite doubts or challenges, knowing that salvation is secure through Christ's finished work.