Matthew 12:43–5 ‘When an unclean spirit goes out of a man, it goes through waterless places, seeking for rest, and does not find it. Then it says: “I will go back to my house, from which I came out,” and when it comes, it finds it empty, swept and in perfect order. Then it goes and brings with it seven other spirits more evil than itself, and they go in and take up their residence there. So the last state of that man becomes worse than the first; so it will be with this evil generation.’
THERE is a whole world of the most practical truth in this compact and eerie little parable about the haunted house. (1) The evil spirit is banished from the man, not destroyed. That is to say that, in this present age, evil can be conquered, driven away – but it cannot be destroyed. It is always looking for the opportunity to counter-attack and regain the ground that is lost. Evil is a force which may be at bay but is never eliminated.
(2) That is bound to mean that a negative religion can never be enough. A religion which consists of shall nots will end in failure. The trouble about such a religion is that it may be able to cleanse people by prohibiting all their evil actions, but it cannot keep them cleansed. Let us think of this in actual practice. People who drink to excess may be reformed; they may decide that they will no longer spend their time in bars; but they must find something else to do; they must find something to fill up their now empty time, or they will simply slip back into their evil ways. People whose constant pursuit has been pleasure may decide that they must stop; but they must find something else to do to fill up their time, or they will simply, through the very emptiness of their lives, drift back to their old pursuits. The lives of these people must not only be sterilized from evil; they must be nurtured to become productive and fruitful. It will always remain true that ‘Satan finds some mischief still for idle hands to do.’ And if one kind of action is banished from life, another kind must be substituted for it, for life cannot remain empty. (3) It therefore follows that the only permanent cure for evil action is Christian action. Any teaching which stops at telling people what they must not do is bound to be a failure; it must go on to tell them what they must do. The one fatal disease is idleness; even a sterilized idleness will soon be infected. The easiest way to conquer the weeds in a garden is to fill the garden with useful things. The easiest way to keep a life from sin is to fill it with healthy action. To put it quite simply, the Church will most easily keep its converts when it gives them Christian work to do. Our aim is not the mere negative absence of evil action; it is the positive presence of work for Christ. If we are finding the temptations of evil very threatening, one of the best ways to conquer them is to plunge into activity for God and for our neighbours.
Barclay; William. The Gospel of Matthew, Volume Two: 2 (p. 59-60). Westminster John Knox Press. Kindle Edition.