Although Gregory Nazianzus and others later attached a specific theological significance to ἐκπορεύεσθαι (i.e., to speak about the unique manner of the Spirit’s coming-to-be from the Father), there appears little reason to believe that John conveys that meaning in 15:26, or that he is deliberately trying to differentiate his ἐκπορεύεσθαι from the Father from his sending from the Son. As Rudolf Schnackenburg writes: The double statement, that is, that Jesus will send him and that he proceeds from
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