Matthew  records Jesus’ lamentation over Jerusalem, “how often would I have gathered you together as a hen gathers her chicks under her wing, but you would not. See, your house is left to you desolate.” Pointing to the temple buildings, he said, “not one stone will be left upon another that will not be thrown down.” His disciples take him aside, apart from the crowds to ask him more about this. When will these things be? He begins to tell them about wars, famines, and earthquakes: these are the beginning of the birth pains (something new is being born). After warning them to flee from Jerusalem when they see these things begin, he announces in extraordinary language:
“And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.”
And just after this, to keep things in the right frame, he tells them “[It] is near, at the very gates… this generation shall not pass, till all these things be fulfilled.” We are still in the first century, the destruction of the temple and of the city in 70AD. Jesus then gives several parables warning the disciples to keep watch, for, again, the time is near. He makes a distinction in each of these between those who keep watch, who are faithful with what they’ve been given, who stay awake and keep their lamps lit, and those who are unfaithful and do not watch. The faithful are blessed, enter the feast, and enter into the joy of the Lord. The unfaithful are cut in pieces and put with the hypocrites, shut out of the feast, and thrown into the outer darkness. He ends this discussion with the parable of the sheep and goat judgment, which begins with the same language he used earlier:
“When the Son of man shall come in his glory, and all the holy angels with him, then shall he sit upon the throne of his glory: And before him shall be gathered all nations: and he shall separate them one from another, as a shepherd divideth [his] sheep from the goats…”
When the Son of man shall come… He isn’t beginning a new topic here. He is pointing back to what he had just said. These are the same words, the same signs, that earlier he made clear would all take place within the lifetime of his hearers. He does not here jump to a final judgment at the end of all time. He is still talking about the coming judgment against Jerusalem and the temple, with the same division he has just laid out in the preceding parables, now between sheep and goats. There will be those who listen to his warning and escape the imminent judgment, and those who do not listen and thus share in the fire and destruction. There will be weeping and gnashing of teeth.
But perhaps I am wrong, and he does shift to the final judgment (without warning). Here, the Protestants will not be happy. Upon what are the sheep and goats judged? Upon their works. The only distinction Jesus points out between the two groups is their treatment of others, how they have acted in the world. If this is the final judgment, then those who fail to do good works are consigned to eternal punishment and those who do them are given eternal life. The final judgment is then a judgment of merit. There is no mention of trusting Jesus, or his works, his blood, his cross, his death. No mention of asking forgiveness for sins, no mention of forgiveness at all. It is a judgment based solely on the merit of the person’s works, plain and simple. Catholics rejoice. But I am being flippant. This parable, along with all these other parables in these two chapters, is not about the final judgment; it is part of the answer to the disciples’ question, “when will these things be?” When will Jerusalem and the temple be destroyed? When is the end of this age, the age of the old, worn-out wineskin, the old covenant under the law? When will the next age begin, the age of the new and better covenant? When you see all these things, it is the beginning of the birth pains, the birth of the new heavens and new earth.