13 Grk “who,” describing the people mentioned in v. 8. A new sentence was started here in the translation by replacing the relative pronoun with a personal pronoun.
14 Or “power,” or “might.” The construction can also be translated as an attributed genitive: “from his glorious strength” (cf. “glorious might”; “glorious strength”; “glorious power”). An allusion to Isa 2:10, 19, 21.

In other versions

They will suffer the punishment of eternal destruction, away from the presence of the Lord and from the glory of his might,

They will be punished with everlasting destruction and shut out from the presence of the Lord and from the glory of his might

They will pay the penalty of eternal destruction from the Lord’s presence and from his glorious strength

They will be punished with eternal destruction, forever separated from the Lord and from his glorious power.

who will pay the penalty of eternal destruction, away from the presence of the Lord and from the glory of his strength,

Who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power;

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