The Offence of the Cross
Paul uses athletic imagery: the Galatians were running well until someone hindered them from obeying the truth. He compares the agitators’ influence to a little leaven affecting the whole lump and denies the rumor that he still preaches circumcision as a requirement. If he did, he says, the “offence of the cross” would disappear. The sharp language of verse 12 shows how seriously Paul views pressure to make circumcision a condition of full belonging.