Whoever is responsible for anything from the Muslims’ issues, and then appoints over them a person due to his love of them, then the curse of Allah is upon him, Allah will not accept from him aversion nor correction until He enters him into the Hellfire.
Prohibition of Nepotism
مَنْ وَلِيَ مِنْ أَمْرِ الْمُسْلِمِينَ شَيْئًا فَأَمَّرَ عَلَيْهِمْ أَحَدًا مُحَابَاةً فَعَلَيْهِ لَعْنَةُ اللَّهِ لَا يَقْبَلُ اللَّهُ مِنْهُ صَرْفًا وَلَا عَدْلًا حَتَّى يُدْخِلَهُ جَهَنَّمَ
Whoever is responsible for anything from the Muslims’ issues, and then appoints over them a person due to his love of them, then the curse of Allah is upon him, Allah will not accept from him aversion nor correction until He enters him into the Hellfire
(Hakim/ Ahmed)
ما من وال يلي رعية من المسلمين فيموت وهو غاش لهم إلا حرم الله عليه الجنة
There is no governor/ wali who takes charge of governing the Muslims, and then dies, and he had been cheating them, except that Allah prohibits him from Paradise
(Bukhari/ Muslim)
Commentary
a. The complete prohibition of any form of nepotism or favoritism in appointing people to positions of responsibility, as indicated by the Prophet صلى الله عليه وسلم that such actions lead to having the curse of Allah سبحانه وتعالى upon one, as well as then being entered into the hellfire.
b. Giving positions to less able people out of love of others or family ties is a treachery to the people since they will be managed by other than the best of them, and is a treachery to the deen since it goes against the order of Allah سبحانه وتعالى and His Messenger صلى الله عليه وسلم.
c. There is a narration from Umar (ra) that the one who does so has betrayed Allah سبحانه وتعالى, and betrayed the Messenger صلى الله عليه وسلم, and all of the believers.
d. In the narration agreed upon by Bukhari and Muslim, it is mentioned that the one who dies having cheated the people with respect to his undertaking, then he is prohibited paradise. Therefore it is clear that cheating is a grave sin particularly for those in positions of responsibility, and to appoint people out of love and family ties rather than ability to leadership roles is a specific type of cheating.