Future Judgment Promises Relief and Locates Vengeance with God

Endurance is a sign of God's justice, not a warrant to strike back

Their perseverance is a manifest token of the righteous judgment of God, that they may be counted worthy of the kingdom of God, for which they also suffer. Worth here is God's verdict on people who suffer for his kingdom, not a claim that pain itself saves. Seeing it is a righteous thing with God to recompense tribulation to them that trouble you, and to you who are troubled rest with us. The sentence assigns both payback and rest to God.

That rest arrives when the Lord Jesus shall be revealed from heaven with his mighty angels. The church is not told to manufacture the fire. Relief is timed to Jesus's revealing, not to the injured person's chance to even the score. A people under affliction are being taught to wait for a public appearing, not to deputize themselves as the flame.

Vengeance in fire belongs to the revealed Lord, not to a human target list

He comes in flaming fire taking vengeance on them that know not God, and that obey not the gospel of our Lord Jesus Christ, who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power. The charge is refusal of God and of the gospel. It describes persistent afflicters and all who will not obey that news. It is not a portrait of Jewish people, not a slur on Israel, and not a license to hunt a modern ethnic, national, or political enemy.

When he shall come to be glorified in his saints, and to be admired in all them that believe — because the team's testimony among them was believed — in that day. The same day that judges also glorifies Jesus in the people who believed the message. The passage does not date that day, and it does not hand the vengeance to readers. Final recompense stays with God.