God wants the Law to be kept, but kept in an extraordinary manner. For we become haughty and puffed up by the righteousness of the Law. And presumption and pride inevitably follow such righteousness, as is clear from unimportant and common examples. For what modest matron or what maiden in the flower of her beauty and youth will you give me who is not puffed up by these gifts? But the insolent arrogance of those who have supreme power and administer civil affairs is boundless. For the righteousness of the Law is something proud and presumptuous. Therefore God confounds it, and when He sees that you are being puffed up beyond measure, He sets it aside and acts in accordance with the righteousness of grace.
Luther’s works, vol. 8: Lectures on Genesis: Chapters 45-50