Well, I've been taught that grace means unmerited favor. So, if God gives us favor without merit of our own, what kind of merit would it take to be worthy of this favor? Why, it must be the keeping of the law, since that's how Christ secured the merit. He lived as we should live, and died as we should die. He rendered reasonable service to God in our behalf, and paid the wages (death) of sin (the transgression of the law), also in our behalf, thus fulfilling the law and establishing it, and also making us free from being under penalty of law. Without the law, there is no need for grace, because without it there would be no offense.