“Remember ye not, that, when I was yet with you, I told you these things? And now ye know what withholdeth that he might be revealed in his time. For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way” (ii Thess.2:5-7). Paul reminds the Thessalonians that he had taught them these things when he was with them.
II Thessalonians, Chapter 2, part 4