Now that’s a mouthful, but its what Peter Kirk and I discussed a little bit a couple posts back in a post entitled, The Attributive Position in Ephesians 4.18.
In Ephesians 4.18, Paul uses the phrase, “ἐσκοτωμένοι τῇ διανοίᾳ ὄντες ἀπηλλοτριωμένοι τῆς ζωῆς τοῦ θεοῦ διὰ τὴν ἄγνοιαν τὴν οὖσαν ἐν αὐτοῖς διὰ τὴν πώρωσιν τῆς καρδίας αὐτῶν” (They are darkened in their understanding, alienated from the life of God because of their ignorance and hardness of heart).
Now there are two questions. For one, which clause does ὄντας go with? While some, including the NA27 & UBS4, places it with “ἐσκοτωμένοι τῇ διανοίᾳ,” there is good reason to consider it as going with ἀπηλλοτριωμένοι. Especially since Paul uses nearly the very same phrase in Colossians 1.21: “καὶ ὑμᾶς ποτε ὄντας ἀπηλλοτριωμένους.”
With that question solved, at least to my liking, the second question is the one that Peter posed. Why did Paul uses this extra participle, ὄντες? Its not in any way necessary. I did a search for other places in the GNT that have a copula participle followed by another participle and could only find false hits.
If these are periphrastic participles, we are still left with the question of significance. Porter is somewhat helpful here when he writes,
Where a choice of the simple and periphrastic forms is available (i.e. in those places where the periphrastic has not replaced a little-used or cumbersome form, e.g. pluperfect), the periphrastic is considered to have the same general meaning as the simple form of the verb. They both grammaticalize the same verbal aspect (i.e. the participle and the finite form use the same tense-form), as well as the same mood (see Chapter 2). However, grammarians who wish to stress that the periphrastic is more emphatic or significant, or that it draws attention to the participle and its modifiers, are probably correct.
Even still, I generally take whatever I read in a grammar with a grain of salt. Unfortunately, I don’t have time to dig through the 40 or so total examples I also found in the LXX & Philo (there are none in the Apostolic Fathers). For all I know they could be false hits too.
Another day perhaps.
If anyone else wants to take this up, they are more than welcome. I can even send you the references if you want.