6 Θαυμάζω ὅτι οὕτως ταχέως μετατίθεσθε ἀπὸ τοῦ καλέσαντος ὑμᾶς ἐν χάριτι [Χριστοῦ] εἰς ἕτερον εὐαγγέλιον, 7 ὃ οὐκ ἔστιν ἄλλο, εἰ μή τινές εἰσιν οἱ ταράσσοντες ὑμᾶς καὶ θέλοντες μεταστρέψαι τὸ εὐαγγέλιον τοῦ Χριστοῦ. 8 ἀλλὰ καὶ ἐὰν ἡμεῖς ἢ ἄγγελος ἐξ οὐρανοῦ εὐαγγελίζηται [ὑμῖν] παρʼ ὃ εὐηγγελισάμεθα ὑμῖν, ἀνάθεμα ἔστω. 9 ὡς προειρήκαμεν καὶ ἄρτι πάλιν λέγω• εἴ τις ὑμᾶς εὐαγγελίζεται παρʼ ὃ παρελάβετε, ἀνάθεμα ἔστω.
There is considerable doubt about the textual readings of Χριστοῦ in v6 and ὑμῖν in v8. Χριστοῦ is omitted by significant Western texts, but not all. Its presence serves only to definitely identify the grace in view. The presence of ὑμῖν in v8 restricts the anathama to a particularly Galatian scenario, rather than a more widespread principle, though such a principle would not be inappropriate. Nevertheless, I retain the reading.
6 I am amazed that are deserting so quickly from the one that called you by the grace [of Christ], to another gospel 7 which is not another [gospel], except there are some troubling you and wishing to pervert the gospel of Christ. 8 But even if we or an angel from heaven preach the gospel [to you] different from what we preached to you, let him be anathema. 9 As we said before and now I say again: if someone preaches to you different than what you received, let him be anathema.
Unlike most of his letters, and letters in general, Galatians omits any thanksgiving and moves directly into astonishment. The cause of his astonishment is not the celerity of their abandoment, so much as the desertion itself, couple with its speed. Theodoret and Chrysostom both highlight that the desertion is spoken of as not ‘from the gospel’ but from God himself, to heighten the immensity of their abandoment. The mention of ‘calling’ here again previews significant latter themes in the letter. The play in vv6-7 about the gospel hinges on the fact that, in Paul’s view, another gospel is, by definition, not a gospel at all. Thus he is forced into speaking of it in one instance as ‘a different gospel’, but then denying its very gospel-like nature, since the message they are turning to is not gospel.
v7 also introduces us more directly to the Galatian Opponents. They are described here as ‘those troubling’ the Galatians, and ‘wishing to pervert the gospel of Christ.’ Paul has no hesitation about casting them in the most negative light possible, since at stake is the very gospel message of Paul, and thus the eternity of the Galatian believers. This leads into the twice-over warning and anathema. ‘We’ in v8 should probably be understood as Paul and his entourage, though the primary originator of such preaching is Paul himself. It is worth noting the complement between ‘different from what we preached’ and ‘different from what you received’. The language of ἀνάθεμα picks up the OT cultic language of given over to destruction, and so indicates falling under the wrath of God in judgment.
It is unclear from the text itself whether ‘as we said before’ should be taken to refer to Pauline teaching in Galatia, which he is seeking to remind them of, or as a communicative device referring simply back to v8, and so simply drawing attention to the gravity of Paul’s warning message.
Paul's opening gambit highlights the main concern, especially of chapters 1-2, that of defending his gospel against the Opponents, who he perceives to be peddling an alternate, and thus deficient and deceptive, 'gospel'. Paul's defence will come in two parts, as he shows both the independent origin and the lack of difference from the Jerusalem apostles, of his gospel.