You act like this is a joke and you meant it that way... but you also knew that Jesus would, in fact, not return in the next 10 minutes. So much so that you were able to make a light-hearted joke about it. There are other things about God and Jesus you know as well. For instance, if I asked you and all Christians around the world to pray together to end all cancer in the world there is no part of you that actually believes that would happen. You might hope, you might say you have faith, but deep down you know it wouldn't happen. You might rationalize the reason for it (not all Christians prayed for the same thing, or there were evil forces working against God neither of which is actually a satisfactory answer as to why you know it wont happen), but you can't really know why in the context of your belief. There is one possibility, however, that fully and completely explains why you know it won't happen.
Christ said certain specific things would happen before He returns. That's not hard for someone that believes and is willing to read to learn about.
It turns out a clear condition is just now for the first time ever becoming close to complete, that all the world would hear the gospel (meaning not only here and there, or just many places, but in all places).
Here's something He said:
43 “You have heard that it was said, ‘Love your neighbor and hate your enemy.’
44 But I tell you, love your enemies and pray for those who persecute you,
45 that you may be children of your Father in heaven. He causes his sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous.
46 If you love those who love you, what reward will you get? Are not even the tax collectors [collaborators with Rome against the Jews] doing that?
47 And if you greet only your own people, what are you doing more than others? Do not even pagans do that?
48 Be perfect, therefore, as your heavenly Father is perfect."
[it being the most perfect response of all to an enemy to do good to them, so then to create change and peace]