Aal-Imran, V104: It is a daleel1 for the obligation of establishing a Hizb (party or group), calling for good (Islam), enjoining what is right and forbidding what is evil.
The directive of enjoining good and forbidding evil is given at a number of instances. At some of these places the directive is addressed to individuals, for instance, in Al-Taubah 9: 71 the believing men and women are praised for their various qualities, one of which is enjoining good and forbidding evil (same is the case in Aal Imraan 3: 110 and Al-Taubah 9: 112). Then again in Luqman 31: 17, Luqman is praised for the sincere advice he gave to his son. His advice included “enjoining good and forbidding evil”. On the other hand, in Al-Hajj 22: 41 one of the responsibilities of the Muslim collectivity, besides a few others, is to enjoin good and forbid from evil. Then again in Aal Imraan 3: 104 the Muslim collectivity (state) is advised to form a group, which is bestowed with state authority, whose prime duty should be to enjoin good and forbid evil.
In view of the above explanation, it should be quite clear that the directive of “enjoining good and forbidding evil” is addressed to individuals as well as the Muslim collectivity.
Another aspect that needs to be clearly understood is the practical nature of the particular directive regarding “enjoining good” and “forbidding evil”. The practical implications of carrying out this directive shall vary with a variation in the position of the person concerned. Under normal circumstances, it should be restricted to a sincere counsel, a soft word of advice or admonition (as mentioned in Al-`asr 103: 3). On the other hand, within an individual’s or a group’s sphere of legal authority, one may use and exert authority to enjoin good and forbid evil. For instance, when a person becomes a father, a guardian or a head of a state etc, he may use his authority over his children, over those who have been put in his care or over the citizens of his state to promote good and to discourage people from any thing that is wrong. Thus, it should be obvious from this explanation that enjoining good and forbidding evil does not inherently imply the use of force. Force can only be used for the purpose where a person has the legal authority to use such force. In all other cases, use of force shall not be allowed and the directive of enjoining good and forbidding evil shall only be carried out by words of advice and admonition.
Now coming to your specific question, it should be clear from the above explanation that the directive in Aal Imraan 3: 104 is addressed to the Muslim state. In this verse, the state or the Muslim collectivity is directed to arrange for a separate state department, like that of the police department or that of the civil defense department, which should be assigned the duty of enjoining good and forbidding evil, on behalf of the Islamic state.
It should also be clearly understood that all such directives of the Qur’an, which are addressed to the Muslim state can and should be carried out only by the state itself. No one besides the state can and should carry out these directives. Thus, the question of whether it is “Fard-al-`ayn or Fard-al-kifayah” does not arise.
2nd March 1999