DEUT900 Because it is so easy for powerful people to become greedy, God tried to ensure that the most powerful person in Jewish society, the king, would not succumb to this natural inclination. Therefore, He forbade the king from taking too many wives (physical desire) or having too many horses (material desire). God also commanded the Jewish king to write an "extra" Torah scroll, to bring it with him wherever he went, and also to study it carefully. In this way, the king will be reminded that he must obey the Torah and not grow haughty, which will lead to greediness [this verse, Deuteronomy 17:15-20]. Unfortunately, as is the case with today's most powerful people, i.e., the CEOs of major companies who earn hundreds of millions of dollars yearly while, at the same time reducing the wages or benefits of their workers, all these safeguards did not prevent most Jewish kings in the past from succumbing to their greedy desires.