The salt cleanses, arrests corruption which impends over the dead masses, sweetens and purifies, and so preserves from decay and dissolution. It works by contact, and within the mass. It thus stands as an emblem of the cleansing which God brings, both in respect,
(a) to that on which it operates,
(b) to the purpose of its application, and
(c) to the manner in which it produces its effects.
(d) That on which it operates.
There is implied here a view of human nature, not flattering but true. It is compared with a dead thing, in which the causes that bring about corruption are already at work, with the sure issue of destruction. This in its individual application comes to the assertion of sinful tendency and actual sin as having its seat and root in all our souls, so that the present condition is corruption, and the future issue is destruction. The consequent ideas are that any power which is to cleanse must come from without, not from within; that purity is not to be won by our own efforts, and that there is no disposition in human nature to make these efforts. There is no recuperative power in human nature. True, there may be outward reformation of habits, etc., but, if we grasp the thought that the taproot of sin is selfishness, this impotence becomes clearer, and it is seen that sin affects all our being, and that therefore the healing must come from beyond us.
(b) The purpose--namely, cleansing.
In salt we may include the whole divine energy; the Word, the Christ, the Spirit. So the intention of the Gospel is mainly to make clean. Preservation is a consequence of that.
(c) The manner of its application.
Inward, penetrating, by contact; but mainly the great peculiarity of Christian ethics is that the inner life is dealt with first, the will and the heart, and afterwards the outward conduct.
