"[§13] The qualifications for the da'wa are based on three things: on knowledge; on God-fearing piety and on governance."

"[§14] The knowledge is divided into two parts: one of which is knowledge of the external, and the other [is knowledge] of the internal. The external has five divisions. One is the science of legal understanding and rulings on the basis of which people are sustained, and religion and the world preserved. It is the foundation of both religion and the da'wa. The second is the science of hadîth, historical reports, narrative accounts, and chains of transmission from the Prophet and the imams. Through it, religion is preserved and the law upheld through the retention of these reports and narrative accounts; they are basis for legal understanding. The third is the science of the Qur'an, its interpretation and explanation, knowledge of the fixed and ambiguous in it, that which is abrogated and what is abrogated, and the command and the prohibition. The fourth is the science of preaching, of memorials and exemplary stories. God, the Exalted, said to His Prophet: 'Summon to the way of your Lord with wisdom and fine exhortation.'²² Exhortation refines the hearts of the people and awakens in them a desire for the afterlife and for religion and withdrawal from this world. The fifth is the science of disputation and discussion by which to encounter, in matters of faith, the heretics, deviants, the philosophers, those who uphold the eternity of the world and the various adherents of false schools of doctrine. Each type has various excellences and they will, if possible, be mentioned at the proper place for them, God willing."

(Source: Klemm, V. and Walker, P. E., A Code of Conduct—A Treatise of the Etiquette of the Fatimid Ismaili Mission, p.42)

22. Qur'an, 16:125