Allah, the Exalted, says:

"Friends of that Day will be foes one to another except Al-Muttaqun: (i.e., pious and righteous persons).'' (43:67)

678. Abu Sa`id and Abu Hurairah (May Allah be pleased with him) reported: Messenger of Allah (PBUH) said, "Allah neither raised up any Prophet nor did He authorize any person with ruling power but for whom there were two types of entourage: one enjoins upon him to do good and incites him to carry it out, and the other enjoins evil and goads him; and the protected (from the bad entourage) is the one whom Allah protects.''
[Al-Bukhari].

Commentary: A ruler has been told here that Taqwa (consciousness and fear of Allah), honesty, integrity and ability are the prerequisites to chosing anybody as his aide or advisor. Prior to their nomination, he should check up the reputation of his advisors. This precautionary measure will serve as a safeguard against the spread of corruption in society and serve the cause of goodness. Secondly, a ruler should obey the Commands of Allah and His Messenger (PBUH) because this discipline will not only keep him safe from making faults but will also serve as a shield against the machinations of wicked people.

679. `Aishah (May Allah be pleased with her) reported: Messenger of Allah (PBUH) said, "When Allah desires good for a ruler, He appoints for him a sincere adviser who will remind him if he forgets and helps him if he remembers. When Allah wishes for him the contrary, He appoints for him a bad adviser who will not remind him if he forgets, nor will he help him if he remembers.''

Commentary: In the recruitment of good and scrupulous aides lies the Blessing of Allah to a ruler because such aides will prove helpful to him in making sound judgements, reaching right conclusions and guarding him against leaning towards evil ways. Yet, if all of these aides are self-seekers, flatterers and corrupt, they will undoubtedly influence his decision-making in a bad way. And one can believe that the end of the ruler will be far from being desirable because history also supports this view. As for the Hereafter, he will be hardly safe from the infernal torment.