This is part of my Exegetical Compilation series which can be found here.
If Ephesians 4:8-10 refers to post mortem salvation to even some degree, that would lend subsequent contextual weight to Eph 4:6 referring to God being both God and Father of all not only in the sense of being authoritatively over all persons (including those currently rebelling) but also authoritatively through all and in all persons (including those currently rebelling), with the parallel implication from the ontological importance of God as unique self-existent Creator of all that God can and will potently bring about reconciliation with those sinners whom He is Father through and in. (There are however some other contextual issues which might weigh toward a more limited application of verse 6 to only current Christians, or neutrally to all eventual Christians which might be a final selection out of all sinners. Please see my extensive comments on that verse and its preceding contexts here.)
Since analysis of these latter verses will have to proceed along several complicated lines, I will be breaking my comments into separate posts for this thread.
Some opponents argue that since “lower” in “lower parts of the earth” is in the comparative and not the superlative, and since the word “of” (for “of the earth”) is not in the original Greek, then Paul must have only been referring to the Incarnation, with the ascent being the Ascension.
First (and this is going to take a while), it’s true that the word “of” doesn’t appear in the Greek, but Greek has no word corresponding to “of” (in this sense) and instead signals that meaning by genitive grammar–and {tês gês} is genitive. “…of the earth” is an entirely standard and uncontentious translation. So this doesn’t read that Christ descended to the “lower earth”, i.e. compared to heaven, but to the “lower parts of” the earth. Which implies a descriptive comparison (if not a contrast) between lower and higher parts of the earth. For which there would be no need, and which wouldn’t make sense, if Paul was only talking about the Incarnation. But it makes good sense if Paul is at least talking about Christ being buried. But then, which captives is Christ leading out from among the dead ones where He was buried?
Granted, a descent in Incarnation fits with the theme of a descent/ascent or humiliation/exaltation Christology which first describes Jesus coming to earth, then ascending to heaven, but so does a descent in Incarnation and then suffering in the Passion to the grave–a theme which no Christian of any stripe denies. By the same token, so would descent into spiritual hades (not merely a physical pit/sheol/grave) fit that theme (much moreso to save His own condemned enemies there!), as an ultimate humiliation in which Christ paradoxically exalts. Why we should stop with such a theme only at the Incarnation and not include at least the Passion and Burial?! But if the burial is included then the concept of Christ rising not merely “from the dead” in a general sense but “out of the dead ones” (which is the sense of the Greek) becomes more important.
In attempting to argue that the phrase “in[to] the lower [parts] of the earth” refers only to the earth as a lower place compared to heaven, opponents may try to claim that the genitive fits a rare situation, of which there are at least two others in Ephesians, where in English translation it switches place with another noun. The intended effect would be that Christ descended to the earth of the lower(s), or to the earth of the lower parts, suggesting that the Earth was the portion of the lower parts Christ descended to.
However, the fairly clear example of this effect at Eph 2:14 doesn’t feature a prepositional phrase followed modified by a genitive phrase. That makes a difference because the debated phrase at 4:9 reads pretty straightforwardly {eis ta katôtera [merê] tês gês} “in(to) the lower [parts] of the earth”, not simply “the lower [parts] of the earth”. If it was the latter, Paul might (but not certainly would) mean “the earth of the lower [parts]”, although that would be an odd way for Paul to talk about earth under heaven (though to be fair Ephesians is stylistically unique in any case!)–but grammatically it’s harder to switch the noun of the genitive phrase with the noun of a full accusative prepositional phrase: “in(to) the earth of the lower parts”. It’s true that 2:14 involves an accusative noun switching place (in English meaning) with a genitive noun, but not from within its own prepositional phrase: “the midwall” is simply the object of the verb, not an object of a preposition as at 4:9.
The same is true at 2:15, which reads literally “nullifying the law of the commandments”: it could read instead “nullifying the commandments of the law” (and probably was intended to mean that, where “the Law” means “the Torah”), but {ton nomon} ‘the law’ is simply a direct object to the verb, not the object-noun of a prepositional phrase.
Much less do instances where English translators move around phrases and terms from their printed order to synchronize with English word-meaning orders, count as examples of this concept. 6:16, for example, puts the verbs, the direct objects, and the genitive description of one of the direct objects, in very clunky places by English grammatic standards, requiring that the phrases and terms be moved around from their printed order to make sense in English: literally “you-shall-be-able all the darts of the evil-one the ones being-firery [or those having-been-set-on-fire] to-extinguish”, but in English grammar “you shall be able to extinguish all the set-afire darts of the evil one”. But unentangling the goofy Greek word order doesn’t require a genitive noun to switch grammatic functions even with a direct object, much less with the object of an accusative or dative preposition.
6:17 again involves untangling weird Greek order in the words and phrases, although not nearly as crazed (by English standards) as in verse 16: literally “and the helmet of the salvation receive, and the sword of the spirit which is a declaration of God”, which doesn’t need much shuffling to fit English grammar construction “and receive the helmet of salvation and [receive] the sword of the spirit which is a declaration of God”. Where does a genitive noun switch places in grammatic function with any noun there in the translation??
But: even if legitimate parallels could be found in Ephesians for switching a genitive noun with an object of an explicit but different kind of prepositional phrase, that wouldn’t mean this verse features that sort of intended meaning. Various levels of context indicate the genitive noun should (maybe) be switched (in English) with the direct object in two verses; otherwise we would read those verses the way the grammar indicates! The contextual argument would have to be solidly established first here, too.