Lightfoot says ‘Paul is distracted between the fear of saying too much and the fear of saying too little. He must maintain his own independence and yet he must not compromise the position of the Twelve.
What was the meaning of circumcision? Circumcision was the sign which God instructed Israel to adopt under the Mosaic covenant, borrowed from the Abrahamic covenant before it. For Abraham it was a seal of the righteousness that he already possessed by faith, for that covenant was a gracious covenant which nevertheless had attached to it elements that were material and earthly and that served as tokens of the real heavenly blessings. The Mosaic covenant borrowed these physical tokens and imported them as elements which were appropriate to that legal covenant. In doing so, it took circumcision which for Abraham was a sign of the righteousness that he already possessed, and translated it into a sign of the righteousness which the eight day old child hoped to possess in following Abraham’s example of faith. It was like taking a wedding ring and using it for a different purpose as an engagement ring in the next generation.