How can we recognize false doctrine?

Jude highlights that those teaching false doctrines do so by separating themselves from the truth of the gospel. They often preach a different gospel that undermines God's sovereign purpose, diminishes the work of Christ, and relies on human effort instead of divine grace. True believers are called to discern these errors by measuring teachings against Scripture, particularly regarding the nature of salvation and the character of God. Jude’s warning serves as a reminder that such teachers may appear within the church yet promote a message contrary to the grace revealed in Christ.