"[§12] The da'wa is a difficult matter and its qualifications are many, including all that God has stipulated in the Qur'an to describe a believer, as well as what the imams have specified in their books concerning the faithful. These things are also required also of the dâ'î. He should have even more of these excellences, and they should be more evident in him. If they do not exist in the believer, his belief is nevertheless possible, but it is not acceptable that they do not exist in the dâ'î. It is as Ja'far b. Muhammad al-Sâdiq said: 'Our knowledge is difficult and considered so; none can bear it other than a prophet sent as a messenger or the closest angel or a believer whose heart God has examined for faith'. The believer is the imam and those dâ'îs and believers who follow him, who have been examined in the da'wa, and who uphold its stipulations. This examination as a rule applies to all the dâ'îs, the hujjas, the imams, the legatees and the prophets, may there be peace upon them all. It is as God said: 'He who created death and life that He might test of you which is best in deeds';¹⁹ and also said: 'And when his Lord tested Abraham with words and he fulfilled them, He said "I am making you a leader (imâm) of the people"';²⁰ and he also said: 'Do the people think that they will be left alone in saying "We believe" and will not be tested',²¹ meaning here 'not examined'?"

(Source: Klemm, V. and Walker, P. E., A Code of Conduct—A Treatise of the Etiquette of the Fatimid Ismaili Mission, p.41)

19. Qur'an, 67:2

20. Qur'an, 2:124.

21. Qur'an, 21:1-2.