He himself said, “He who testifies to these things says, ‘Yes, I am coming soon’" Revelation 22:20 Apostle John replied, "Amen. Come, Lord Jesus.” Revelation 22:20. That was written 2,000 years ago, so Christians wonder what did Jesus mean by soon. Even the apostles thought he was coming back in their lifetimes.
AFAIK, the soonest that was predicted by a reputable source is 2060 by Sir Isaac Newton, but Christians have to be ready if it happens tomorrow. I thought it would be after our passing, but now I have change my mindset and think it could be tomorrow.