This scenario seemingly being conveyed has not come yet - some two thousand years after Jesus' disciples passed from this earth. Was Jesus really discussing a time thousands of years into the future as he spoke to his disciples concerns about their future as he spoke with them 'privately' (Matt. 24:3)?
Why should they be concerned about some event that was going to happen more than two thousand years from now? Are they future historians or something?
Put it this way: Would you be concerned about something that will happen more than 2,000 years from now?
The intention of the early Roman Catholic translators was to infer the end of the world was just around the corner - in order to keep their followers in a state of fear. This gave them the ability to control their members - which was the purpose of Constantine's creation of the Roman Catholic Church in the first place.
Translated as such some 300 years after Jesus spoke this, this institution wanted as they created this impression that Jesus, John and Daniel were discussing the coming end of the whole world, rather than the Jewish-Roman wars that spanned over 60 years following Jesus' passing. This interpretation was meant to instill fear and a sense of urgency to join the Church.
But then the end of the world didn't come - together with judgement day - despite so many early bishops and popes having predicted it. This created a philosophical problem for the Church because the assumption was that everyone would be judged at the end of the world as well. So what happened to those who died before the end of the world?
To cover their problem they came up with purgatory. This speculative notion states that those who die before judgement day will have to hang out in some kind of limbo state until judgement day comes.
This would mean - after 2,000 years - that billions upon billions of people are floating around this limbo purgatory state. Where are they? And how are they floating around if their physical bodies are not decomposed? Is there a cave somewhere where literally hundreds of billions of people are waiting for judgement day? If so, why haven't any of the exploration teams - who have been drilling hundreds of miles deep and descending into caves and mines - found them?
The reason is because this state of purgatory is fiction. Yes, people do move on after the death of their physical bodies. But they move on to their next destination, depending upon their consciousness and activities within this lifetime.
Yes, each of us is judged at the end of this lifetime, and this judgement determines are next destination.
This means that judgement day occurs for each individual at the end of our physical lifetime.
This also defines "the end" - the end of our physical lifetimes, when our physical body dies and we leave it behind.
Or, a person may have chosen during their lifetime to follow Jesus' instructions and focus their lives upon learning to love and serve God. At the end of their physical lifetime such a person journeys home to the spiritual realm: This is the "gospel of the kingdom" Jesus is discussing in the above verse.
Rather than the end of the world, Jesus' statement above specifically refers to the "end" as being the time of death. The word being translated to "end" is the Greek word τέλος (telos). The lexicon defines τέλος as "termination, the limit at which a thing ceases to be - always of the end of some act or state, but not of the end of a period of time." This is the time of death. This is the moment when the body ceases to be alive, and the eternal spiritual being leaves the body.
Furthermore, Jesus was giving his disciples an instruction in this verse: The translation to "shall be preached" comes from the Greek word κηρύσσω (kēryssō), which means according to the lexicon, 'to herald,' 'to proclaim,' 'to publish'.
This translation "shall be preached" is worded in a third-person manner, but there is no substantiation for this. Jesus is speaking directly and privately with his disciples. He is instructing them. He is telling them he wants them to preach his teachings to others.
The translation to "whole world" is also translated quite liberally and out of context. The word "world" is being translated from οἰκουμένη (oikoumenē), which can mean 'world,' or 'Greek world' but primarily was used during those days to refer to the lands of the Roman empire: "the portion of the earth inhabited by the Greeks, in distinction from the lands of the barbarians;" or "the Roman empire, all the subjects of the empire."
So Jesus is not making some broad proclamation about Christian evangelists over a thousand years later traveling around the world to preach, followed by the end of the world coming. If this were true, then the world would have ended many centuries ago, after Christian preachers sailed around the world and violently converted many indigenous peoples to their sectarianism.
Rather, what is being communicated by Jesus to his disciples privately is the following of a simple but important instruction to his disciples. Here is a more appropriate translation of this verse:
"Teach this gospel of the spiritual world throughout the land, and give testimony to all people until the end of your days."
This translation is consistent with Jesus' teachings. Jesus was teaching a specific message that he wanted his disciples to pass on. His message was clear:
"'Love the Lord your God with all your heart and with all your soul and with all your mind.' This is the first and greatest commandment." (Matt. 22:37-38)
(For a translation of Jesus' statements from the Book of Matthew without institutional sectarian influence, see the Gospels of Jesus - translated from the original Greek texts.)