One of my more perceptive students this week called my attention to the curious phrase “the Spirit of Jesus” (τὸ πνεῦμα Ἰησοῦ) in Acts 16.7. The only other usage of this construction in the NT is found in Phil 1.19, in which Paul implores the help of τοῦ πνεύματος Ἰησοῦ Χριστοῦ. So what are we to make of this?
We must, of course, remember that a fully-fledged Trinitarian schema did not develop for quite some time even after the writing of the New Testament; in particular, the distinction between the Son and the Spirit lagged considerably behind efforts to distinguish the Father from the Son. To take just one example, Justin Martyr, writing in the middle of the second century, more or less entirely fails to distinguish between the identities and activities of the Word (that is, the Son) and the Spirit (cf. Anthony Briggman, “Measuring Justin’s Approach to the Spirit: Trinitarian Conviction and Binitarian Orientation,” VC 63 (2009): 107–137). Given that it is not until the fourth century that we find the Son and Spirit clearly distinguished, we should not be surprised to find some confusion concerning the unique identity of the Spirit as distinct from the person of the Son in a first-century text like Acts.
However, this may not, upon further reflection, be the best way to tackle this text. Following F. F. Bruce (Acts NICNT, 327), I take it as more probable that, given the reference to the “Holy Spirit” in the previous verse (16.6), this must be Luke’s way of indicating a different method of communicating the will of the Spirit. Given the close link with Jesus, I suspect that 16.7 more likely refers to some kind of charismatic prophecy in which the speaker is understood to be speaking in the name of Jesus and under the possession of the Spirit. Given that we have to imagine some kind of process by which “the Spirit of Jesus did not allow them (to go into Bithynia),” this mechanism seems plausible and it also makes sense of the unique expression.
As for Phil 1.19, this brings us into a broader discussion of the relationship between Christ and the Spirit in Paul, and we again need to recall that, for Paul, the Spirit “is identical with the exalted Lord once this Lord is considered, not in Himself, but in His work towards the community” (so Schweizer, TDNT 6.433). Trying to go deeper, however, we are confronted with the problem of whether “Spirit of Jesus Christ” should be taken as an objective or subjective genitive, but it seems to almost certainly be objective (cf. Gal 4.6). Perhaps, as Fee (Philippians NICNT, 134-5) suggests, the unusual designation can only be explained by the context: “Paul knows that Christ will be glorified in his life or death only as he is filled with the Spirit of Christ himself. That is, it is Christ resident in him by the Spirit who will be the cause of Paul’s–and therefore the gospel’s–not being brought to shame and of Christ’s being magnified through him.” Fair enough, but I’d still like more clarification on why Paul uses “Spirit of Jesus Christ” instead of his much more common “Spirit of God.” Alas, it remains to me a bit of a mystery…