Note 14 at 2 Th. 2:7: "Iniquity" is the Greek noun ANOMIA, and literally means the condition of being without law (Thayer). Lawlessness is going on but someone or something is restraining it.

Note 15 at 2 Th. 2:7: This is the point that the apostle John made in 1 John 2:18 when he said, "Little children, it is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time." The spirit of antichrist is already at work in the world. Anyone who is against Christ has this spirit of antichrist working in them. But that spirit is not and cannot find its full expression as long as the restraining influence is still present (see note 13 at v. 6).

Note 16 at 2 Th. 2:7: The word "letteth" is the same Greek word used in verse 6 for the English word "withholdeth." Something or someone is restraining and holding back the progress of lawlessness. This must be taken out of the way for the wicked one to be fully revealed.