One must then look into the conditions of leadership without which one’s leadership is invalid. We found them as follows:
(1) That he be ṣalībah [paternally-related] from Quraysh. Allāh’s Messenger ﷺ informed that the leadership is among them. (Sahih Muslim 1820)
(2) That he be bāligh [mature-minded], mumayyiz [able to distinguish].Allāh’s Messenger ﷺ said:
«The pen is lifted from three, and he mentioned a sleeping person until he awakens, the child until he matures and the insane person until he recovers.» (Sunan al-Tirmidhī 1423)
(3) That he be male. Allāh’s Messenger ﷺ said:
«A people who assign their amr [authority] to a woman will not succeed». (Jami` at-Tirmidhi 2262)
(4) That he be Muslim. Allāh ﷻ said:
{Allāh will never make for the disbelievers over the believers any way} (4:141),
and the Khilāfah is the greatest way. He ﷻ also commanded the belittling of Ahl Al-Kitāb, the taking of the Jizyah from them, and the killing of those not of Ahl Al-Kitāb until they become Muslims.
(5) That he be knowledgeable of his duties, obedient to Allāh ﷻ, not causing any corruption in the land. Allāh ﷻ said:
{Assist one another upon duty and piety and do not assist one another upon sin and transgression} (5:2),
and whoever put forth one who did not obey Allāh ﷻ and caused corruption in the land or was not trustworthy and had no knowledge of his religion, then he assisted upon sin and transgression and did not assist upon duty and piety. Allāh’s Messenger ﷺ said:
«Whoever does an act that is not in accordance with this matter of ours will have it rejected». (Sahih Muslim 1718)
(6) That he not be ignorant, (7) or be weak, (8) or be incapable. The Prophet ﷺ said:
«Abū Dharr (رضي الله عنه)! You are indeed ḍa‘īf [weak]. You must not have command over two. You must not be walī [entrusted] to the wealth of the orphan» (Sunan Abi Dawud 2868).
Allāh ﷻ said:
{But if the one who has the obligation is of limited understanding or weak or unable to dictate himself, then let his guardian dictate in justice.} [2:282].
There is thus no doubt that one who is ignorant or ḍa‘īf, or one who is incapable to do something, then he must have a walī [one entrusted over him], and whoever must have a walī over him is not allowed to be the walī over all Muslims [since he could not be the walī over his walī, which is contradictory].
The appointment of one who does not meet these eight conditions is invalid. It is not permissible nor is it legally binding at all.
Then: It is mustaḥabb [recommended, preferred] that (1) he be knowledgeable of specific matters of worship, politics, and all rulings, (2) he performs all obligations, (3) he avoids all major sins, both privately and publicly, and (4) he conceals his minor sins. It is makrūh [disliked] that a person is entrusted to the Ummah who does not comprise of these traits. But if such a person is indeed appointed, his appointment is authentic though disliked, and he must be obeyed in his obedience to Allāh and not obeyed in disobedience to Allāh.
The ideal situation is that (1) he cooperates with the people without weakness, (2) he is severe in rejecting vices without leniency, (3) he be wakeful, (4) not careless, (5) courageous, (6) not restricting wealth from its rightful owner, (7) and he does not waste anything inappropriately. All of this can be summarized to be: that he establishes the rulings of the Qur‛ān and the Sunan of Allāh’s Messenger ﷺ, including every excellent trait.
There is no harm if the imām has any defect in his physical being, whether he is blind, deaf, disfigured, leprous, lacking two hands or two feet; or if he has reached old age, as long as he is in his right mind, even if he was a hundred years old; or if he had an epileptic spell and then recovered; or if he was given allegience right after reaching maturity; as long as he meets all conditions of leadership, then such leadership is permissible. There is no text from the Qur‛ān, nor Sunnah, nor Ijmā‘, nor deduction, nor any other form of evidence restricting such people. Instead, Allāh ﷻ said: {Be qawwāmūn [upright, establishing maintainers] of equity}, so whoever establishes equity has complied with what he was commanded.
No one from the people of Islām [i.e. any Muslim] disagrees that inheriting the leadership is not allowed, nor that it is not permissible for one who has yet to mature, except for the Rawāfiḍ: they permit both matters. There is no disagreement, however, that it is not permissible for a woman; and by Allāh ﷻ we are empowered.
Source: [Ibn Ḥazm, Al-Fiṣal Fi’l-Milal Wa’l-Ahwā‛ Wa’n-Niḥal, 4/128-129]. Translated by Abū Ḥassān.
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