It’s part of a scripture in 1 Thessalonians ch.4. It’s referring to the return of Jesus. It is actually called the day of the Lord. On that day, the earth as we know it ends. Jesus is returning to reign and rule over the earth. It’s to give hope to believers. They thought in the first century that the saints who died weren’t part of the resurrection in Christ. Paul wrote that the Lord will return in the clouds and the dead in Christ will rise first. And those who are alive will be caught up with Him in the clouds. And it is also referring to those who gave their hearts to God and died to themselves. Yes, I am part of those who are dead in Christ. I die daily. Where do you stand?