by John M. Frame
The lecture materials on decalogical hermeneutics are rather abstract, and you might wonder if they have any practical value, besides making the Larger Catechism look more sensible.
The main practical point of it, I think, is this: what Scripture requires, essentially, is a new heart. That heart is given by grace, but God’s Spirit progressively cultivates it until it fully becomes what it essentially is, a heart consecrated to God and obedient to him. Thus there is a fundamental unity to biblical ethics. Biblical commandments are concerned with forming the heart, and each does it for a different angle.
That single heart-quality may be called “love.” Or it may be described in many ways, each of which characterizes the whole. The “new heart” is a heart which sets no gods before the Lord, which worships no idols, which speaks no blasphemy, and so on. You can understand, then, why if you keep one commandment perfectly, you will thereby keep all the others. And if you disobey one, it detracts from your obedience to the others. There is a single heart-attitude in all obedience, and a single attitude involved in all sin.
Sometimes when we do a job we divide it neatly into parts: do this part first, leaving the others aside for the time being. Then move on to the others.
The living of the Christian life is not like that. You cannot work on your attitudes toward authority, for example, leaving everything else aside until you have perfected that area; for if you do that, your attitude toward authority will always be defective. (One who respects God’s authority wants to hear and obey every word that proceeds from God.) Rather what we need to do is to hear everything God says and seek to obey at each moment.