shaken
“Shaken” translates the Greek verb σαλεύω (saleuō), which is usually used in the passive voice referring to something being shaken and unsettled from a previously secure position. It is used in the New Testament to describe God’s shaking the powers of the heavens during the tribulation period (cf. Matt 24:29; Mark 13:25; Luke 21:26), to describe a foundation being unsettled as by an earthquake (cf. Luke 6:48; Acts 16:26), or figuratively of people being shaken from a previous peaceful state (cf. Acts 17:13) or even from a settled understanding (as here). The word is consistently translated with “shake” or “shaken” everywhere it appears in the New Testament. Here, Paul urges the Thessalonians not to allow themselves to be shaken from their previous understanding of the Day of the Lord by new, alarming rumors. Rather, they should hold fast to the firm foundation of teaching from God with which Paul had originally instructed them.

in your mind
“In your mind” is a more literal translation of the phrase ἀπὸ τοῦ νοὸς (apo tou noos) than something like “from your composure.” Paul, in using the word “mind,” is speaking here of sound thinking and reasoning. They already have sound teaching regarding the end times, and Paul is emphasizing that they are not to let sensational rumors shake them from a right and sound understanding of what they already know.

alarmed
“Alarmed” translates the Greek verb θροέω (throeō). The word only occurs three times in the New Testament, all in eschatological contexts (cf. also Matt 24:6; Mark 13:7). This translation of θροέω (throeō) differentiates it from ταράσσω (tarassō), which is a more general term and is translated as “disturbed” in Acts 15:24 and Galatians 1:7 and 5:10 to refer to the Judaizers.

exhibiting
“Exhibiting” translates ἀποδείκνυμι (apodeiknymi), which is an intensified form of the verb δείκνυμι (deiknymi), which communicates the idea of showing, displaying, or making something known. To communicate the intensification, it is translated here as “exhibited,” which is a stronger English word than the more general “show” or “display.” Thus, the verb here describes a person who is flagrantly exhibiting himself as being God. This is the incredibly blasphemous action of the “man of lawlessness,” who, Paul explains, must come before the Day of the Lord takes place. Such a person has not appeared yet, and so the Thessalonians can be confident that they are not currently living in the Day of the Lord.

will be revealed—…coming—
The dashes set off the coming of Lord Jesus to slay the antichrist more sharply, which does two things: (1) Helps the reader see that the antichrist’s coming and not Jesus’ is spoken of in verse 9; (2) brings out Paul’s emphasis to the Thessalonians that the antichrist is in a way already defeated.

WILL SLAY WITH THE BREATH OF HIS MOUTH
These words are formatted in caps because Paul is alluding to an Old Testament text here found in Isaiah 11 (specifically v. 4). In that chapter of Isaiah, the prophet describes the Messiah, who will render just judgment and put the wicked to death with the breath of His lips. Paul uses very similar wording here to call that text to mind as he explains that the true Christ will triumph over the antichrist. The formatting of this translation helps readers recognize that Paul is drawing on this logic from the Old Testament so that they may go back and ensure they understand what this Psalm is teaching in order to better track Paul’s argumentation here.

sends
“Sends” more accurately brings out the present tense of the Greek verb πέμπει (pempei). This emphasizes the ongoing action of the Lord to carry out His plan both for believers and unbelievers.

deluding influence
As the footnote indicates, a more literal rendering of this phrase is “a work of delusion.” Careful attention to the footnotes aids the reader in seeing the intentional connections which cannot be as clearly be brought out in translation. Paul’s point is that just as the restrainer is now working (vv. 6–7) and Satan is now working (vv. 7, 9), so God the Father is now working. This theme of working is prevalent in verses 6–11, as Paul describes not just the Day of the Lord, but what is happening in the present moment regarding believers who are not in the Day of the Lord. Thus, many factors are at work, but God is ultimately at work to ensure the outworking of His plan for His people.