What does the Bible say about the church at Sardis?

In Revelation 3:1-6, the church at Sardis receives a somber message from the Lord Jesus, who acknowledges their works but condemns them for having a reputation of being alive while being spiritually dead. This stark contrast highlights the danger of maintaining a façade of faith without the vital substance of spiritual life, leading to a call for vigilance and repentance. The passage serves not only as a message to Sardis but as a cautionary reminder for all believers to examine their spiritual state and ensure that they are genuinely alive in Christ.