Matthew 28:19 – KJV, “Go ye therefore, and teach all *nations*, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost”.
The Greek word for nations refers to a multitude of people that you’re associated with, i.e. maybe you’re a doctor, then you belong to a nation of doctors, therefore, God is sending you to be a king and priest among the doctors; maybe you’re student go and demonstrate the kingdom power and authority among your fellow students.
1 Corinthians 15:23-25 says “But every man in his own order: Christ the firstfruits; afterward they that are Christ’s at his coming. Then cometh the end, when he shall have delivered up the kingdom to God, even the Father; when he shall have put down all rule and all authority and power. For he must reign, till he hath put all enemies under his feet”.
The kingdom is in the hands of Jesus now, however, very soon He will have to hand it over to the Father, and when He does that the end will come up.
The Bible is also showing us that King Jesus Christ must reign till He has put all His enemies under His feet, He must put down all rule, all uathority and power. Everything that exists must be made subject to Him, the kingdom must have dominate all spheres of the universe.
But how is Jesus going to reign in the world? As believers, we are His Body, the Flesh of His Flesh and the Bone of His Bone. Therefore, if Jesus is to reign on earth, He will do it through us.
The end will come when the Body of Christ has arisen in power and authority and trampled over the systems of the earth.