Our Lord calls the sinful the children of the wicked one--that is, of the devil. But he does not mean that the devil created them, for he can create no one; no, God created us all, and has, furthermore, redeemed us all with his precious Blood. There is something about them, though, which the devil may be said to have created, and that it is which makes them his children. It is sin, which he first brought into God's creation, to which he tempted our first parents, and to which he is all the while tempting us now. Sin is the devil's work; and sinners are his children, because they do his work.
But few people, at least few Christians, are all the time sinners and children of the devil. Sometimes they repent and become, at least for a time, children of God. Good and evil are mixed up in them, as they are in the world. So our Lord's parable is true of each one of them as it is of the world at large. Each of our hearts is a little field in which God is sowing the good seed of his holy inspirations, and the devil the bad seed of his wicked temptations; and sometimes consent is given to one, sometimes to the other.
Perhaps we may have asked ourselves the question (for it is a very natural one to ask): "Why has God allowed the devil to sow his bad seed in the world and in the hearts of men? And why, if he lets it be sown, does he not root out this bad seed, and not let it grow and choke what is good?" I should not wonder at your asking this question, and you should not wonder if we cannot give all of God's reasons for it, for it is one of the mysteries of his providence. But he has himself given one reason for it in his explanation of this parable. The servants, you will remember, wanted to go and root out the cockle; but the master said: "No, lest while ye gather up the cockle, you root up the wheat also together with it." Would it not be so with us, too, if God should take away all the bad seed of temptation out of our hearts? A great deal of our virtue would be rooted up, too, and what was left would not be very strong and solid. You can see that often. A person seems very good, but what is the reason? It is because he is not much tempted. { 110} Let a strong temptation come, and perhaps such a person will sin more easily than one who has seemed much worse, but has really been acquiring solid virtue by faithfully combating with difficulties the other has not had. And not only would our virtue not be solid, but our merits would not be very abundant, without temptation; for most of our merit is gained by resisting sin.