ISB ~ 2 Thessalonians 1 v9

eternal destruction:Not annihilation or the termination of existence, but an everlasting state of spiritual death, disinheritance, and damnation. For Paul, hell is nothing less than eternal separation from the peace and presence of the living God.

Other biblical ideas and images fill out the picture of this terrifying prospect:the damned will endure “tribulation and distress” (Rom 2:9), “eternal punishment” (Mt 25:46), and “unquenchable fire” (Lk 3:17; cf. Is 66:24) (CCC 1033-36).

See word study: Hellat Mk 9:43.