Man has in his nature a weakness, and that is that when anything is given to him for his good, and when he likes it, he becomes attached to it until he gets its bad results; and, once he is attached, he never wishes to leave it. If a physician gives a drug to his patient and the patient likes it, he indulges in it, and wishes to continue it, until, instead of a medicine for his cure, it turns into a vice for his destruction. So idolatry became a vice, until the Messengers had to fight it and break it with the hammer. But in cases where it has remained as a first lesson, it has made a great improvement, and has made people much more capable of receiving the second lesson of the God-Ideal, which for many has been difficult to learn.