_Fourth Grade._ In this grade instruction was given in the history of God’s revelation. The age of the world is divided into seven stages, each under the guidance of a prophet whose teaching surpassed that of his predecessors and abrogated it. Between each pair there were but “silent” guides who did not add to nor alter the revelation of the prophet who inaugurated that age. Each of these seven prophets had a coadjutor who was his authorised exponent to mankind at large. These seven prophets and coadjutors were— (_i._) Adam, with coadjutor Seth. (_ii._) Noah, with coadjutor Shem. (_iii._) Abraham, with coadjutor Ismaʿil. (_iv._) Moses, with coadjutor, at first Aaron, then Joshua. (_v._) Jesus, with coadjutor Simon Sifa (Cephas). (_vi._) Muhammad, with coadjutor ʿAli. (_vii._) al-Kaʾim, with coadjutor ʿAbdullah. Thus the seventh prophet al-Kaʾim, _i.e._, Ismaʿil or his son Muhammad, has abrogated the teaching of the Prophet Muhammad, and has given a new revelation. At this point, therefore, the convert was entirely separated from orthodox Islam which accepts Muhammad as the “seal of the prophets,” that is to say, the final completer of revelation, and was taught to regard his religion as obsolete. _Fifth Grade._ In this grade it was taught that the traditional practices of the religion of Islam were merely temporary, a concession to the uninstructed multitude who could not yet understand the spiritual principles of _iman_: they were useful as an educative influence with the ignorant, but the Qurʾanic precepts on which some of them were based had an esoteric meaning quite other than their literal form, whilst the traditional rules which had added so much detail to the laws of the Qurʾan were baseless and negligible. The disciple was taught to replace the external precepts of Islam by inner convictions. If he was a Persian he was reproached with the servile submission which the Persians had rendered to an Arab Khalif: if he were an Arab he was instructed that the privileges of the Arabs have now been transferred to the Persians. In addition to this he was taught certain principles of geometry and the properties of numbers, all applied in a mystical manner to the claims of the Imamate. He was further informed that each prophet had twelve _hujjaj_ corresponding to the twelve signs of the zodiac, to the twelve months of the year, to the twelve tribes of Israel, and to the twelve _nugabaʾ_ whom Muhammad chose from the _ansar_ or “helpers” at Madina. These numerals “seven” and “twelve” which have been shown to possess sacred meanings, were now cited to explain why men have twelve dorsal vertebrae, seven cervical vertebrae, etc. It is as well to note that when these teachings were first put forth the other Shiʿites who followed Musa and his successors had not yet made up the number of twelve Imams.