What are the required characteristics of a just ruler (Hakim)?

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The ruler must be strong yet devoid of tyranny, and lenient without being weak. He must not covet what is false, nor should the weak despair of his justice. The ruler must possess patience (hilm), deliberation, sagacity, and alertness, ensuring he is never caught unawares or deceived by guile. He must have sound hearing and sight, possess knowledge of the languages of the people under his jurisdiction, be chaste (afif), pious (wara'), incorruptible (nazih), far from avarice, truthful in speech, possessing good judgment and consultative ability. His speech must be gentle when approaching, inspiring awe when threatening, and faithful when promising. He must not be tyrannical or oppressive, as this prevents those with valid arguments from presenting them.