Galatians 5:11

‘But as for me brothers, if I still preach circumcision why am I still persecuted? Then the stumblingblock of the cross has been done away.'

Some may have pointed at cases like Timothy's where he had allowed circumcision. And he no doubt still allowed Christian Jews to circumcise their sons if they wished to. But they then accuse him of ‘preaching circumcision' by his actions. Thus he is at pains to defend himself. He points out that he suffers persecution precisely because he preaches the message of the cross as the only way of salvation, and rejects anything else as necessary for salvation. That is the stumblingblock of the cross, the fact that it does away with all merit and all deserving, that it brings all under the curse of God. It is that it tells us that the only way that we can be put in the right with God is by looking to One Who died on a cross, openly under God's curse. It requires submission on the basis of total unworthiness. It rejects any attempt by men to contribute to their own salvation. The reason that the cross is a stumblingblock is because by it all else, and especially circumcision, is put in its proper place as not being essential. From a salvation point of view it is irrelevant, no matter what it is. It says that all must be accepted as cursed. Thus all ordinances and good works are excluded as contributing to salvation. Such ordinances, including circumcision, may be all right for those whose customs they are, as long as that is all that they make of it, but they must not be magnified into something supremely important, something essential to being saved. As Paul tells us elsewhere, what he is saying may be foolishness to men (1 Corinthians 1:18; 1 Corinthians 1:21) but in it is revealed the wisdom of God.