https://youtu.be/62Vc-YuaogE
https://youtu.be/CXCKpCVQHxI
https://youtu.be/SfnsmizBFdA
Sardis was a church not unlike churches today. They had brought the world into the church and corrupted the mission of the church. They were dead in many ways and even the few faithful were dying. Jesus Christ sends them and any church that follows their ways a very stark warning: repent or face judgment. This messages speaks to all churches of all time to make sure they stay on point and preach the Bible and glorify Christ alone.
Jesus addresses the Church at Ephesus and commends them for their works and discernment. But He also reveals that they lost their first love for Him and they must repent. This is a warning to all churches of all time that we must keep our passion and zeal in loving the Lord our God supremely.