'Imam 'Ali (AS) said to 'Umar b. al-Khattab, 'There are three things which if you observe and act in accordance with, they will suffice you in everything else, and if you abandon them, nothing else will benefit you other than them.' 'Umar asked, 'What are they Abu al-Hasan?' He (AS) said, 'The observance of penalties for the close and the distant, ruling according to the Book of Allah, be it with acceptance or discontentment, and to divide fairly between the black and the red.' 'Umar said, 'By my life, you have summarised and explained [everything].'