This is a symbol of baptism, which now saves you-- not the putting away of the filth of the flesh, but the answer of a good conscience toward God, through the resurrection of Jesus Christ,
The problem with this interpretation, from my viewpoint, is that Scripture nowhere else makes baptism a condition for salvation. In fact, it consistently warns against adding anything to faith for salvation. Circumcision did not save children under the Old Covenant any more than baptism does under the New Covenant. Circumcision expressed the faith of the parents. Abraham received the sign of circumcision to demonstrate his faith on the male members of his household (Genesis 17).