“They who, in their obedience, attain to the greatest height which is possible in this life, are so far from being able to supererogate, and to do more than God requires, as that they fall short of much which in duty they are bound to do” (XVI. 4).
They say that the “greatest height” of obedience nevertheless, falls short of doing more than God requires. Correct. For God requires a perfect obedience and a perfect satisfaction to His holy law. So how on earth is the WCF “strengthening their assurance” (XVI. 2) by means of this obedience that falls short of much which in duty they are bound to do? A true biblical assurance needs no “strengthening,” because it is founded upon the Rock of Jesus Christ’s atoning blood and imputed righteousness. The WCF, on the other hand, needs to strengthen their own assurance that is founded upon the shifting sands of their own self-righteousness efforts which they call “good works” in their ignorant zeal.