Here the crucial change occurs: But now. The readers’ present situation is stated in strong contrast with their previous condition, before their experience with Christ. The new situation is described at length in the following verses.
In union with Christ Jesus (Good News Translation, New English Bible; Translator’s New Testament “through union with Christ Jesus”; Barclay “because of your relationship with Christ Jesus”), literally “in Christ Jesus” (Revised Standard Version, New International Version, and others). This clause may also be translated by “because you are one with Christ Jesus” or “because you are so close to Christ Jesus.”
Far away … near: the Gentiles were “far away” from Zion, the visible dwelling of God with his people; now they are “near,” like the Jews (see also verse 17). It is pointed out that the language reflects Isaiah 57.19, where those “far away” were the Israelites in exile, distant from Jerusalem. In Rabbinic teaching “to come near” was used of the reception of a Gentile convert into the Jewish faith.
There is a basic problem involved in the order of the various elements in verse 13. The first part of the verse refers to present time, while the second part refers to a past experience. The third part, however, again brings the focus of time into the present, but by reference to the sacrificial death of Christ, which was in the past. This produces a particularly awkward development if references to time must be made rather specific and if the phrase by the sacrificial death of Christ must be rendered as a clause. It may be better therefore in some languages to shift somewhat the order of phrases and clauses, for example, “you used to be far away, but now that you are in close union with Christ Jesus, you have been brought near, because Christ died as a sacrifice on the cross” or “… because Christ shed his blood for you.” At the same time, however, there is a problem involved in the figurative reference to being far away and being brought near. In some languages it is necessary to specify more precisely the relative position, and therefore it may be best to translate “who used to be far away from God” and “have been brought near to God.”
By the sacrificial death of Christ: literally “in the blood of Christ”; for “blood” see 1.7.
Quoted with permission from Bratcher, Robert C. and Nida, Eugene A. A Handbook on Paul’s Letter to the Ephesians. (UBS Handbook Series). New York: UBS, 1982. For this and other handbooks for translators see here .