Exactly when the Christian church began to teach the return of Jesus is something to look forward to is unclear. That doctrine is most likely founded on a misunderstanding of Matthew 24 especially verse 30, “At that time the sign of the Son of Man will appear in heaven, and all the tribes of the earth will mourn. They will see the Son of Man coming on the clouds of heaven with power and great glory.” Overlooking the surrounding verses gives the illusion of a could rider that we see in much of the artwork that depicts this. But even in this verse we see the people will mourn because they will finally understand what is happening.