We can assign three parts to the Great Commission.
1) Preach the Gospel as a witness to all the nations.
2) Make individual disciples in each nation.
3) Make whole nations disciples.
I think many christians would read #1 and stop there. I’ve had christians declare to me that the end is near because the gospel has been preached throughout the whole world, and Jesus said, “(T)his gospel…will be preached in all the world as a witness to all the nations, and then the end will come.” (Matthew 24:14)
I would argue against that reasoning, firstly and simply because, the Great Commission, as given to us in Matthew 28:18-20, does not say “go and preach the gospel as a witness to all nations.” It says to “go and make disciples of all nations.” There is a large difference between getting the gospel out there to be heard (a witness) and getting whole nations of people to conform their entire lives to it (discipleship).
Secondly, I would argue that, with the statement Jesus made in Matthew 24, He was not referring to the Great Commission, nor was He referring to the end of the world. Again, His wording did not imply the fullness of the Great Commission when He referred to the gospel as going out as a witness to all nations; that is part of the Great Commission, yes, but only the first part. Also, when Jesus used the word “world” in vs 14 (through the Holy Spirit inspired author), He used the Greek word oikoumené, which means “the portion of the earth inhabited by the Greeks, in distinction from the lands of the barbarians”; so arguably, He was referring to the Roman Empire only, not the entire planet 2000 years into the future.
The conversation in Matthew 24 between Jesus and the disciples was about the destruction of the temple, or more broadly, the end of the Judaic age, temple sacrifice, and the Mosaic priesthood. When Jesus said the gospel would go out to all the Roman Empire and then the end would come, I would argue that He was primarily thinking about all the Jews scattered throughout the empire at that time. Jesus wanted the Jews to hear the gospel before the destruction of the temple in 70 AD. He wanted them to understand what was happening and why the temple was destroyed. It was destroyed because there was no longer any need for it and because judgment had come on the unbelieving Jews. The “end” which Jesus referred to is that destruction and judgement.
So, back to the Great Commission. Jesus said that all authority has been given to Him, and that is the reason we are to go out and make disciples of all nations. He did not say, “People are dying and going to hell, so go and preach to as many as possible and then I’ll come back”. Jesus is king, and we are to declare that fact to the world, and teach people how to serve the king. To do this, we have to do all three parts of the Great Commission. We can’t stop after #1 thinking we’ve finished the job. The bible does not teach that or allow it.