However, because Moses gave you the practice of circumcision (not that it came from Moses, but from the forefathers), you circumcise a male child on the Sabbath.
Then God gave Abraham the covenant of circumcision, and so he became the father of Isaac and circumcised him when he was eight days old, and Isaac became the father of Jacob, and Jacob of the twelve patriarchs.
What I am saying is this: The law that came four hundred thirty years later does not cancel a covenant previously ratified by God, so as to invalidate the promise.