ruler
“Ruler” translates ἄρχων (archōn), which is simply the word to indicate someone who has authority or ruling capacity. Because of this, the more general term “ruler” is better than something more specific like “prince.” The ruler in view here is Satan, who has authority and power over “the air”—likely a reference to the realm inhabited by the demons under Satan’s command. In this verse, Paul is emphasizing Satan’s rulership to communicate the hopeless and helpless position of those dead in their transgressions and sins, subjected under his wicked authority.

the spirit
While “air” designates the realm of Satan’s authority, “spirit” speaks of his influence within that realm. Though his demonic hosts, he works in, or influences, those who live in constant rebellion against God (the sons of disobedience). They are enslaved to his control, helplessly subjugated to his authority and influence. Here, “the spirit” is set in apposition with “the air,” demonstrating Satan’s realm of authority and how he works within that realm. He rules both the power of the air (his demonic host) and the spirit (the activity or working of that host to influence disobedience to God).

conducted
“Conducted” is from ἀναστρέφω (anastrephō). While the word can generically mean “live,” here it more accurately has the sense of “to conduct oneself in terms of certain principles” (see BDAG on ἀναστρέφω). In other words, prior to salvation the believer lived by nature in accordance to the guiding principle of the lusts of their flesh. This translation as “conducted” rather than “lived” also provides consistency in translating the Greek term so that readers can recognize it more easily where it appears.

doing
“Doing” translates ποιέω (poieō), and is the most consistent rendering for this verb in this translation. It carries the generic sense of “doing,” “creating,” or “accomplishing” something, and Paul’s point here is that prior to salvation, believers were actively doing whatever they desired in their flesh.

by grace you have been saved⁠
The interjectory phrase, “by grace you have been saved” is set off with dashes rather than parentheses. This small change puts more emphasis on the importance of this statement. While parentheses can communicate something that is seen more as background information simply to be assumed, the use of dashes puts this statement more in the foreground, as Paul cannot continue before interjecting with this important doctrine, which he will further elaborate in verses 8–9. To Paul, it is important enough to break his sentence structure and to say twice, so this translation seeks to bring out that emphasis as clearly as possible.

this
The translation, “this not of yourselves” rather than “that not of yourselves” more accurately renders the near demonstrative pronoun τοῦτο (touto). Translating the pronoun literally as “this,” shows that it points back to something mentioned immediately prior. Because its grammatical gender is neuter and not feminine (like “grace” or “faith”), it is best seen as referring to the entire previous statement of verse 8. Thus, It is this salvation as a whole, not just the faith or the grace here, which is “the gift of God” and not a result of any human work.

not of works
While some translations have something like “not as a result of works,” the simpler phrase “not of works” more literally conveys the Greek wording (οὐκ ἐξ ἔργων; ouk ex ergōn) by removing superfluous words. This is maintained as “not of works” rather than more of a change to “not by works” to avoid altering a very familiar passage where the meaning is accurately conveyed by something closer to what is most familiar.

citizenship
“Citizenship” translates πολιτεία (politeia). This is the word’s primary meaning and refers to the right of someone to be a member of a sociopolitical entity. What Paul is saying here is that prior to being in Christ, Gentiles had no right to citizenship among the people of God. But now they have been brought near by Christ’s blood (v. 13) to join in with those of Israel, who are now together being made into “one new man” as a unified body and people of Christ (vv. 14–16).

dividing wall of the partition
The translation “dividing wall of the partition,” rather than something like “barrier of the dividing wall,” better matches the Greek word order. It is also clearer regarding Paul’s point that in Christ the historic partition between Jews and Gentiles—the Law—has been abolished.

making
The translation “making” peace rather than “establishing” peace brings out the literal meaning of the word ποιέω (poieō; “do,” “make,” “produce”). Consistency in translating this term is important, as it also appeared in the previous verse. There, Christ “made” both groups one by abolishing the enmity so that, here, He might create the two into one new man, “making” peace. This puts the emphasis on Christ’s own work in accomplishing these things.

in Himself
The translation “in Himself” reflects Paul’s language of believers being “in Christ” in Ephesians. It also brings out the fact that Christ bore the penalty of the Law in Himself on the cross so that there might be reconciliation between and salvation to Jews and Gentiles.

joined
The translation as “joined” for συναρμολογουμένη (synarmologoumenē) provides a more vivid sense of what Paul is describing here than something like “fitted.” Though “fitted” is not a poor translation, “joined” communicates a more active sense, as Paul pictures all of the various and diverse parts of Christ’s church coming and being built together into a unified structure which is the holy sanctuary of the Lord. Paul will use the same term again in 4:16, where it is translated the same way.

sanctuary
As is customary in this translation, ναός (naos) is translated as “sanctuary” to distinguish it from “temple” (ἱερόν; hieron), which refers to the overall structure and grounds of the temple complex (cf. Matt 4:5). “Sanctuary” here brings out Paul’s point that believers are not just spiritual temple structures—they become a very dwelling place of God (cf. v. 22), as was the Holy of Holies within the physical temple.