Галатам 5:12

they . . . which trouble you--Translate, as the Greek is different from Gal 5:10, "they who are unsettling you." were even cut off--even as they desire your foreskin to be cut off and cast away by circumcision, so would that they were even cut off from your communion, being worthless as a castaway foreskin (Gal 1:7-8; compare Phi 3:2). The fathers, JEROME, AMBROSE, AUGUSTINE, and CHRYSOSTOM, explain it, "Would that they would even cut themselves off," that is, cut off not merely the foreskin, but the whole member: if circumcision be not enough for them, then let them have excision also; an outburst hardly suitable to the gravity of an apostle. But Gal 5:9-10 plainly point to excommunication as the judgment threatened against the troublers: and danger of the bad "leaven" spreading, as the reason for it.

In this chapter the apostle comes to make application of his foregoing discourse. He begins it with a general caution, or exhortation (Gal 5:1), which he afterwards enforces by several considerations (Gal 5:2-12). He then presses them to serious practical godliness, which would be the best antidote against the snares of their false teachers; particularly, I. That they should not strive with one another (Gal 5:13-15). II. That they would strive against sin, where he shows, 1. That there is in every one a struggle between flesh and spirit (Gal 5:17). 2. That it is our duty and interest, in this struggle, to side with the better part (Gal 5:16, Gal 5:18). 3. He specifies the works of the flesh, which must be watched against and mortified, and the fruits of the Spirit, which must be brought forth and cherished, and shows of what importance it is that they be so (Gal 5:19-24). And then concludes the chapter with a caution against pride and envy.

5:12 mutilate themselves (literally cut themselves off; cp. Phil 3:2): Paul uses biting sarcasm and wordplay with multiple levels of meaning: (1) Paul might be alluding to pagan priests in the province of Galatia who castrated themselves in devotion to pagan gods. An insistence on circumcision for Christians is essentially no different. It involved cutting the flesh to become acceptable to God by physical deeds rather than by faith in Christ. (2) Depending on circumcision mutilated the false teachers’ standing before God, so they might as well mutilate themselves physically. (3) In the old covenant, emasculated men were not allowed to enter the congregation (Deut 23:1); similarly, those who rely on circumcision have no place in the new covenant community. Paul probably wished that the Judaizers would cut themselves off by removing themselves from the community.