For long these traditions circulated orally, the authority of each depending on the person who first gave it and the reliability of the chain (_isnad_) of men who had passed it on from him. At first this tradition was regarded as explanatory of, or at the most supplementary to, the teaching of the Koran. Early Moslem teachers pointed to the Jews as having two law-books--the _Taurat_ and the _Mishna_--while Islam had only one--the Koran. But opinion changed, the value of tradition as an independent revelation came to be more highly esteemed until at last it was seriously discussed whether a tradition might not abrogate a passage of the Koran with which it was at variance. The writing of traditions was at first strongly discouraged, and for more than a century the stories of the Prophet's conduct passed from mouth to mouth. Had all the narrators been pious men, this might have been tolerable, but this was not the case. The Omayyad dynasty was not a pious one. Men who were not religious but wished to appear so invented traditions to justify their manner of life. The sectarians did not hesitate to adopt the same means of spreading their own teaching. Many Moslem writers testify to the fact that forged traditions were circulated, and that religious opinion was confused thereby. The need for some sort of authoritative collection seems to have been felt by the one pious Omayyad caliph, Omar II. (717-720), who is said to have ordered Ibn Shihab uz-Zuhri to make such a collection. Of this work, if it was carried out, we know nothing further. It was, however, by a man born during this reign that the first systematic collection of traditions was made--the _Muwatta`_ of Malik ibn Anas (q.v.). Yet this work is not a book of tradition in the religious sense, it is really a corpus juris and not a complete one. The object of Malik was simply to record every tradition that had been used to give effect to a legal decision. The work of sifting the vast mass of traditions and arranging them according to their relation to the different parts of religious life and practice was first undertaken in the 3rd century of Islam (A.D. 815-912). In this century all the six collections afterwards regarded as canonical by the Sunnites (orthodox) were made. By this time an immense number of traditions was in circulation. Bukhari in the course of sixteen years' journeying through Moslem lands collected 600,000, and of these included 7275 (or, allowing for repetitions, 4000) in his work. The six collections of tradition received by the Sunnites as authoritative are: (i) The _Kitab ul-jami` us-Sahih_ of Bukhari (q.v.) (810-870). This is the most respected throughout the Moslem world and most carefully compiled (ed. L. Krehl and T. W. Juynboll, Leiden, 1862--and frequently in the East; also with many commentaries. French translation by O. Houdas and W. Marcais, Paris, 1903 sqq.).