31 “When the Son of Man comes in His glory, and all the holy angels with Him, then He will sit on the throne of His glory.
32 “All the nations (1484 ἔθνος ethnos) will be gathered before Him, and He will separate them one from another, as a shepherd divides his sheep from the goats.
33 “And He will set the sheep on His right hand, but the goats on the left. (Matt. 25:31-33 NKJ)
Did Christ say “all the nations [of the world]” will be judged, or “all the [Christian] nations” will be judged?
For example, Christ says the kingdom will be given to a “nation” (1484 ἔθνος ethnos) meaning Christians: “Therefore I say to you, the kingdom of God will be taken from you and given to a nation (1484 ἔθνος ethnos) bearing the fruits of it” (Matt. 21:43 NKJ). Peter also used “nation” to refer to Christians in 1 Peter 2:9 “But you are a chosen generation, a royal priesthood, a holy nation (1484 ἔθνος ethnos).” Therefore, “All the Nations” can mean “all the nations [of Christendom]” or more precisely, “all the people” [who heard the Gospel of Christ and were therefore liable for not obeying it.]
That is how some in the early Church interpreted it:
If, after all this, we cannot suppose that a judgment of non-Christians is here meant, we may even go still further, and say that non-Christians are not included at all, and so we must also reject the view usually adopted, since Chrysostom and Augustine, that what is here exhibited is a judgment of all men, believers and unbelievers alike. For, so far from the mention of the divine ἐκλογή, ver. 34, or the idea of the δίκαιοι, ver. 37, or what Jesus says at ver. 35, or the answer of those assembled before the Judge, vv. 37 and 44, or the entire omission generally of any distinction between belief and unbelief, harmonizing with the notion of a mixed body consisting of Christians and non-Christians, they entirely exclude the latter. We should therefore return to the very old view (Lactantius, Instit. vii. 20; Jerome, Euthymius Zigabenus), which, though it had been neglected in consequence of the prevalent eschatology, was preserved by Grotius, the view, namely, that what Jesus is here depicting is the judgment of Christians: περὶ τῶν Χριστιανῶν δὲ μόνων ὁ λόγος ἐνταῦθα, Euthymius Zigabenus, who proves this, above all, from vv. 35, 36. All the points previously adduced as arguments against the other explanations combine to favour this view.-Meyer, H. A. W. (1884). Critical and Exegetical Handbook to the Gospel of Matthew (W. Stewart, Ed.; P. Christie, Trans.; Vol. 2, pp. 178–179). T&T Clark.
Context supports this early Christian Interpretation. “Goat-like behavoir” is seen in the Five Virgins foolishly failing to greet the Bridegroom when He came (Mt. 25:1-13) and in the “wicked and lazy servant” who did nothing for the Kingdom of God (Mt. 25:14-31). After saying these parables, Christ talks about the Judgment of the Sheep and the Goats. Isn’t it reasonable He is still talking about those who should have been ready for His arrival? That can’t be said about “all the nations [of the world],” it can only be said about ‘All the nations [liable for having heard the gospel of Christ].”
Moreover, it would violate Christ’s principle that those who did not know God’s will receive severe punishment of eternal flame (Lk. 12:47-48; Mt. 25:41-45). Only those who know what God requires, and fail to do it would be judged so harshly.
The proof “all the nations” cannot refer to all the population of the earth, is found in the context of the New Testament:
The judgment of the Sheep and the Goats happens at Christ’s return, not after the 1000-year millennial Kingdom. Also, unlike Judgment Day when the dead are raised from the Sea, Death, and Hades (Rev. 20:11-15) , no resurrection occurs in Matthew 25: 31-46.
Furthermore, the Sheep cannot be Christians because this Judgment occurs while they are seated with Christ and His angels, as Kings and Priests. “These my Brethren (Mt. 25:40; Rm. 8:29) were “gathered” (2 Thess. 2:1) from the earth during Christ’s coming in glory. They reign with Christ as Kings and Priests (Rev. 1:6; 20:4-6; 1 Thess. 4:14-18; 1 Cor. 15:51-58; Mat. 24:29-31; Rev. 14:14-16). Because they believed in Christ when physically alive, they do not “come into judgment, but has passed from death into life.” (John 5:24). As Christ’s “Brethren” they have authority to judge the unsaved with Christ (Mt. 19:28; 1 Cor. 6:3; Rev. 20:4), the “firstborn among many brethren” (Rm. 8:29).
Both the Sheep and the Goats know Christ, they call Him LORD. They know Christ’s disciples but had not joined them in the Faith. King Jesus decrees if they received His disciples (Mt. 12:40) they have received Him. Those who helped His brethren during the Great Tribulation would receive their reward (Mt. 10:42; Mk. 9:41), entry into the Kingdom of God.
Therefore, “all the nations” refers to all the survivors of Armageddon from all nations that heard the Gospel of Christ, but failed to do it. Christ judges those who practiced Christianity as having professed faith in His Name, and He invites them to join “Christ’s brethren” seated there with Christ—all the Christians who were raptured at Christ’s coming and were then serving as His Kings and Priests (Rev. 1:5-6; 5:10). Its implied the Sheep were “translated” like Enoch (Heb. 11:5) “; changed” “in the twinkling of an eye” (1 Cor. 15:51-52) when they join the redeemed (Dan. 12:3; Mt. 13:43).
Then the goats are cast into the lake of fire to join the Beast and False Prophet (Mt. 25:41, 46; Rev. 19:20; Compare Mt. 8:10-12; 13:24-30, 36-42; 22:1-14; 24:45-51; 25:24-30).
The rest of the earth who had no connections to “Christ’s brethren” (which implies they had not heard the gospel preached sufficiently to incur liability for not believing it), enter the 1000-year kingdom of Christ. They marry and populate the earth resulting in billions more of humanity to enter the New Heavens and New Earth of God’s Kingdom (Rev. 21:1-8). Although aging has ceased, they do not have eternal life at this time. They must first pass the final test of the earth (Rev. 20:7-15); until then they counted as still “dead” (Rev. 20:12; John 5:25).
Their judgment is ongoing. If anyone sin during the Millennial Kingdom they are cast off accursed, which means tossed into the lake of fire:
19 I will rejoice in Jerusalem, And joy in My people; The voice of weeping shall no longer be heard in her, Nor the voice of crying.
20 “No more shall an infant from there live but a few days, Nor an old man who has not fulfilled his days; For the child shall die one hundred years old, But the sinner being one hundred years old shall be accursed.
21 They shall build houses and inhabit them; They shall plant vineyards and eat their fruit.
22 They shall not build and another inhabit; They shall not plant and another eat; For as the days of a tree, so shall be the days of My people, And My elect shall long enjoy the work of their hands.
23 They shall not labor in vain, Nor bring forth children for trouble; For they shall be the descendants of the blessed of the LORD, And their offspring with them.
24 “It shall come to pass That before they call, I will answer; And while they are still speaking, I will hear.
25 The wolf and the lamb shall feed together, The lion shall eat straw like the ox, And dust shall be the serpent’s food. They shall not hurt nor destroy in all My holy mountain,” Says the LORD. (Isa. 65:19-25 NKJ)