The sheep and goats are two classes of people among the Nations. In this present age all sheep and goats are together, both saints and sinners, the righteous in Christ and the unrighteous. A nation is a group of individual people. Sheep are the people who belong to God, true believers of Christ, both Jews and Gentiles. The sheep are the righteous, those who are righteous are saved by grace through faith in Christ and not of works, they are saved to do good works.
Goats are unbelievers, hypocrites, sinners among every nation.
The goats are the unsaved and will experience eternal punishment. Sheep are a symbol of humbleness and obedient submissiveness to the leading of the Shepherd and His guiding. Goats are a symbol of riotous, unconsciously selfishness, failing to see the needs of others. Jesus is the Lamb of God offered for the redemption of sin and the Goat offered for atonement of sins , in the Law given to Moses. The separation of the sheep and the goats illustrates a truth.