John Calvin Commentary Matthew 25:32

"and before him shall be gathered all the nations: and he shall separate them one from another, as the shepherd separateth the sheep from the goats;" — Matthew 25:32 (ASV)

And all nations shall be assembled before him. He employs large and splendid titles to extol his kingdom, so that the disciples might learn to expect a different kind of happiness than what they had imagined. For they were satisfied with this single consideration, that their nation was delivered from the miseries with which it was then oppressed, so that it would be clear that God had not in vain established his covenant with Abraham and his descendants. But Christ extends much further the benefit of the redemption brought by him, for he will be the Judge of the whole world. Again, in order to persuade believers to holiness of life, he assures them that the good and the bad will not share alike; because he will bring with him the reward which is laid up for both. In short, he declares that his kingdom will be fully established, when the righteous will have obtained a crown of glory, and when the wicked will have received the reward which they deserved.

As a shepherd separateth the sheep from the goats. When our Lord says that the separation of the sheep from the goats is delayed until that day, he means that the wicked are now mixed with the good and holy, so that they live together in the same flock of God. The comparison appears to be borrowed from Ezekiel 34:18, where the Lord complains of the fierceness of the goats, which attack with their horns the poor sheep, and destroy the pastures, and pollute the water; and where the Lord expressly declares that he will take vengeance. And therefore Christ’s discourse amounts to this: that believers ought not to think their condition too hard, if they are now compelled to live with the goats, and even to endure many serious attacks and annoyances from them; secondly, that they ought to beware of being themselves infected by the contagion of their vices; and, thirdly, to inform them that in a holy and innocent life their labor is not in vain, for the difference will one day appear.