undeserved generosity of God, to which they respond in adoring trust: the grace-faith reciprocal. That is how it has always been with God, and always will be. God’s grace: all of him for us. Our faith: all of us for him. Such is the covenant. And God gives circumcision as a tangible proof of the validity of this covenant between God’s free acceptance of Abraham and Abraham’s free acceptance of God. Notice one thing more about this mark of the covenant. It was strictly enjoined, as we have seen, but