Galatians 6: 12-13.” As many as desire to make a fair shew in the flesh, they constrain you to be circumcised; only lest they should suffer persecution for the cross of Christ. For neither they themselves who are circumcised keep the law; but desire to have you circumcised, that they may glory in your flesh.”
Making a show in the flesh refers to circumcision and to the outward rituals of Judaism which any unsaved man could keep without being restricted otherwise. Weak Christians were tempted to go back to Judaism because they could escapte persecution and more easily conform to the outward appearance of righteousness without really commiting themselves to anything.
The Judaizers desired that Christianity become just another Jewish sect, reflecting on all the outward working of keeping the Law, and bringing glory (they thought) to Judaism itself.