Jesus assigned us to “make disciples of all nations.” Not individuals from all nations, but all nations.
“Nation” in Matthew 28:19 is the Greek word ethnos. According to the Dictionary of Biblical Languages with Semantic Domains, “ethnos” means “a people, a large group based on various cultural, physical or geographic ties.” (We must not confuse “people group” with the modern concept of a geo-political state. For instance, Ethiopia, a geo-political state, is home to over 100 people groups.)
We are to disciple people groups, not simply individuals. That clearly suggests that the task will be complete, not when there is an evangelistic witness in each nation, but when the world’s people groups are discipled.
The word ethnos (race, nation, people group) is derived from ethos, “the distinctive character, spirit, and attitudes of a people” (Collins English Dictionary ). A culture’s ethos includes its worldview, sacred belief system, value system, first principles and habits of the hearts of the people.
It is ethne (the plural form of ethnos) or people groups that we are to disciple. Given the nature of discipling (life on life) and nations (a people group), we must disciple ethne at the level of culture. We are to bring biblical values – truth, beauty, and goodness – into the consciousness of the people group.

Too often we think of discipleship as teaching new Christians to be spiritual: to pray, to read the bible, to worship and fellowship together and to witness about Christ. These are all essential but not sufficient to completing the task.
We must build on this foundation to disciple nations at the level of culture. While we are teaching people to pray and read the Bible, we must also teach them … to honor Christ as Lord of all of life, … to engage all the domains–family, government, education, commerce, the arts and media–with His Lordship in view, … to bring biblical truth, beauty and goodness to their culture. While the process of discipling begins with individuals, it is nations, or people groups, that are to be discipled!
Matthew Henry (1662-1714) was an English Puritan perhaps best known for his commentaries on the whole Bible, works bound not by modern sensibilities of individualism but by the more biblical frame of community. In his commentary on Matthew 28:16, he wrote:
Do your utmost to make the nations Christian nations; not, “Go to the nations, and denounce the judgments of God against them, as Jonah against Nineveh, and as the other Old-Testament prophets’’ (though they had reason enough to expect it for their wickedness), but “go, and disciple them.’’ Christ the Mediator is setting up a kingdom in the world, bring the nations to be his subjects; setting up a school, bring the nations to be his scholars; raising an army for the carrying on of the war against the powers of darkness, enlist the nations of the earth under his banner. (Matthew Henry’s commentary on the whole Bible : Complete and unabridged in one volume)
– excerpted from a forthcoming book by Darrow Miller