“That they all might be damned who believed not the truth, but had pleasure in unrighteousness.”
King James Version (KJV)
2:12 That they all may be condemned - That is, the consequence of which will be, that they all will be condemned who believed not the truth, but had pleasure in unrighteousness - That is, who believed not the truth, because they loved sin.
2Th 2:12 Be damned. Because "they had pleasure in unrighteousness".