Natural law in the Sermon on the Mount
Some brief observations from the Sermon on the Mount in Matthew 5-7 in relation to natural law. Is Christ’s ethic a way of undermining and subverting the natural order, or restoring and fulfilling it? Or something else entirely?
Salt
What does Christ assume in saying of his disciples that they are the salt of the earth? Salt has a nature, and it has a proper end, and salt is bad when it fails to achieve its proper end, that is, adding flavour to the things it is applied to. Salt not only has a proper end in itself, but it is also an agent that is used to bring other things (namely, meals!) to their full glory.
In comparing the lives and works of his disciples to salt, Christ is implicitly relating their ethics to their natures, and to the natures of the things to which they will be "applied".
Fulfilment of law
Jesus describes his ministry as fulfilling the law, not abolishing it.
It is worth considering that one of the purposes of the Law of Moses was to draw the attention of the nations to the wisdom that Israel had access to. Perhaps part of Jesus’ fulfilment of the law is related to his embodying in himself (and amongst his disciples) the wisdom that Gentiles would recognise as good, as it accords with the law of nature known to all nations.
Habit
As Jesus draws our attention not only to murder and adultery, but to the hidden sins of hatred and lust in the heart, we might recall Hemmingsen’s discussion of virtue as a habit:
Cicero defines virtue, [aretē (Gk.)], in the following way: "Virtue is a habit of the mind consistent with nature, moderation and reason." The ancients, moreover, define it thus: "Virtue is the art of living well and correctly." To this is opposed vice, [kakia (Gk.)], a habit of the mind that according to the judgment of nature, conflicts with right reason. [Niels Hemmingsen, On the Law of Nature: A Demonstrative Method, 103-104]
Obedience to these words of Christ necessarily requires us to pay attention to our habits of mind, our attitudes, our reflexive responses to uncalled-for stimuli and so on, so that even they conform properly to God’s law. Put another way, Christ is not impressed by our avoidance of adultery so long as we are habitually lustful in our hearts.
The corollary of this teaching comes later in the sermon, as Christ teaches us not to make a public display of our virtue for the praise of others.
Non-resistance
Christ’s commands about non-resistance (e.g., turning the other cheek) most readily lend themselves to an anti-natural (or at least, non-natural) take on his ethics.
The willingness to suffer, in the context of the gospels, seems to me to be dependent upon a certainty that God will, in due time, vindicate his people. At least in that respect, it does turn on matters that we know about from special revelation, rather than from natural revelation.
However, insofar as our willingness to suffer is an outworking of our faith in God, it isn’t anti-natural at all: nothing is more natural than for a creature to recognise his creatureliness and his dependent upon the Creator for everything. This is to be in touch with the reality of the natural order at the most fundamental level.
Is it natural to love one’s enemies? Clearly, this would not have been possible in the state of integrity, there being no human enemies. So, withholding the judgment that is due to someone does seem to be an outworking of grace plain and simple. It seems too much to say that this undermines nature, but it surely goes beyond the demands of natural justice in some way.
Trees
Similar to his use of salt imagery discussed above, Christ’s use of tree imagery also turns on nature. The relationship between a tree and its fruit is a very natural one, as we learn in Genesis: trees bear fruit after their own kind. In time, you can tell who the bad trees are because of the fruit that they bear.
Wisdom
Wisdom themes are present throughout the sermon on the mount, but they become most explicit right at the sermon’s end. But notice how high the stakes are: while we are accustomed to thinking of wisdom as leading to relative wealth rather than poverty, or relative happiness rather than sadness, Jesus employs the dichotomy between them to make a contract between entering the kingdom or not!
This is not utterly unprecedented: for example, Proverbs does a young man’s pursuit of the adulterous woman as a path towards his own death. Nonetheless, Jesus takes these categories from Proverbs, and warns the entire nation of Israel that they not choose the foolish path that leads to destruction, and that they make the wise choice of hearing and obeying his voice, crying out in the streets, while there is still time.
These are some written reflections from a reading done in my Natural Law & Scriptural Authority class for my M.Litt program.