It is the stealing itself which delights a thief, for it presents him with the challenge of proving to himself how clever he is, and, at the same time, how stupid and careless his victims are. Obviously the immediate motive is to retain more money. Here is the special danger of theft. It involves deceit and cunning. We are well aware that when somebody commits an evil, the more deliberately he does so, and the more premeditation there is, the more serious an evil it is.
Theft normally involves a great deal of premeditation.
It requires planning and careful thought. He plans and goes over his crimes many times before committing them. His whole mind is absorbed in the sins he is going to commit. So it is that his whole mind, his whole spirit, is rapidly poisoned with evil. Indeed deceit, especially when it involves the hypocritical use of precious and holy things, can poison the very remains of good and truth within a man.