2 Thessalonians 1:8a → Isaiah 66:15

Paul describes the Lord Jesus "revealed from heaven in blazing fire" (en pyri phlogos), drawing on Isaiah 66:15 where Yahweh comes "in fire" (baesh) and "his chariots like the whirlwind, to render his anger in fury, and his rebuke with flames of fire." Isaiah 66 portrays the final theophanic judgment at the end of the book, when God separates the faithful from the rebellious and establishes the new heavens and new earth (66:22). Paul applies this Yahweh-theophany directly to Christ's parousia, maintaining the fire imagery as the instrument of divine vengeance. The "blazing fire" is not merely atmospheric description but theophanic tradition rooted in Sinai (Exod 19:18), the burning bush (Exod 3:2), and the pillar of fire (Exod 13:21) — God's self-disclosure always involves fire as a mark of his holiness and judgment. By casting Christ's return in Isaiah 66's language, Paul identifies the parousia as the eschatological theophany Isaiah anticipated, when God's long-deferred final judgment is executed. The connection also imports Isaiah's context of distinguishing between true worshipers and hypocrites — the fire tests and separates, just as Paul distinguishes between those who know God and those who do not (2 Thess 1:8b).