VERSE 31. So then, brethren, we are not children of the bondwoman, but of the free. With this sentence the Apostle Paul concludes his allegory of the barren Church. This sentence forms a clear rejection of the righteousness of the Law and a confirmation of the doctrine of justification. In the next chapter Paul lays special stress upon the freedom which the children of the free woman enjoy. He treats of Christian liberty, the knowledge of which is very necessary. The liberty which Christ purchased for us is a bulwark to us in our battle against spiritual tyranny. Therefore we must carefully study this doctrine of Christian liberty, not only for the confirmation of the doctrine of justification, but also for the comfort and encouragement of those who are weak in faith.