The Enemy Is Already Inside

This sermon examines the urgent shift in Jude's letter from a planned discussion on common salvation to a necessary warning against infiltrators who have breached the church's perimeter. The central message calls believers to earnestly contend for the faith, defined as the unchanging gospel core of Christ's death, burial, and resurrection, rather than engaging in debates over secondary traditions or preferences. The tone is pastoral yet combative, urging the congregation to view themselves as soldiers in a spiritual war who must identify deception while maintaining a winsome and compassionate approach to those who are deceived. The speaker emphasizes that the faith was once delivered to the saints and must be preserved and passed down without alteration, requiring believers to know the genuine truth well enough to spot lies in the current cultural climate. Questions: 1. Why did Jude change his mind about what he originally intended to write to Christians? 2. What does Jude mean when he tells believers to "earnestly contend for the faith"? 3. How can Christians fight for the truth without becoming argumentative or unkind? 4. What does the Bible mean when it speaks of "the faith" rather than simply having faith? 5. How can we tell the difference between essential Christian doctrines and matters of personal preference? 6. Why does Jude warn Christians about enemies who have already entered the church? 7. What does it mean that the faith was "once delivered unto the saints"? Can Christianity change with the times? 8. Is defending the Christian faith the responsibility of pastors and theologians, or does every believer have a part