This verse seems to say that people are cast into the furnace at “the end of the age”. I always thought that it was in the next age. I’m confused!
“Again, the kingdom of heaven is like a dragnet that was cast into the sea and gathered some of every kind, which, when it was full, they drew to shore; and they sat down and gathered the good into vessels, but threw the bad away. So it will be at the end of the age. The angels will come forth, separate the wicked from among the just, and cast them into the furnace of fire. There will be wailing and gnashing of teeth.” Matthew 13: 47
First, of what “age” is Christ speaking here? Answer: the age of the Old Covenant dispensation, which was to end with the overthrow of Jerusalem and the destruction of the temple (Matthew 24:1-35).
Second, who are the “wicked” in view? Answer: the first-century generation of unbelieving Jews which Christ declared would not escape the “condemnation of Gehenna” (Matt 23:32-36).
Third, what did Christ mean by being “cast into the furnace of fire?” Answer: this figurative language is borrowed from the Hebrew Scriptures. In Ezekiel 22:17-22 (cf. Isaiah 31:9) we read:
"And the word of the LORD came to me: “Son of man, the house of Israel has become dross to me; all of them are bronze and tin and iron and lead in the furnace; they are dross of silver. Therefore thus says the Lord GOD: Because you have all become dross, therefore, behold, I will gather you into the midst of Jerusalem. As one gathers silver and bronze and iron and lead and tin into a furnace, to blow the fire on it in order to melt it, so I will gather you in my anger and in my wrath, and I will put you in and melt you. I will gather you and blow on you with the fire of my wrath, and you shall be melted in the midst of it. As silver is melted in a furnace, so you shall be melted in the midst of it, and you shall know that I am the LORD; I have poured out my wrath upon you.”
Although the judgment of which Christ speaks took place at the “end of the age,” its effects have continued on throughout the age that followed (i.e., the age of the Messianic reign), as the “house” of the Jewish people (i.e., the temple) remains left to them “desolate” (Matt 23:37-38). In this sense the punishment into which they entered at this time has been an “age-abiding” (aionion) one (Matt 25:46). They remain still today “destroyed from the presence of the Lord,” as they understood it (2 Thess 1:5-10).