The Talmud relates mainly to the affairs of everyday life--the laws of buying and selling, of making contracts--also to external religious observances, on all of which the most meticulous details are given. As a Jewish writer has expressed it: ... the oddest rabbinical conceits are elaborated through many volumes with the finest dialectic, and the most absurd questions are discussed with the highest efforts of intellectual power; for example, how many white hairs may a red cow have, and yet remain a _red_ cow; what sort of scabs require this or that purification; whether a louse or a flea may be killed on the Sabbath--the first being allowed, while the second is a deadly sin; whether the slaughter of an animal ought to be executed at the neck or the tail; whether the high priest put on his shirt or his hose first; whether the _Jabam_, that is, the brother of a man who died childless, being required by law to marry the widow, is relieved from his obligation if he falls off a roof and sticks in the mire.[18] But it is in the Cabala, a Hebrew word signifying "reception," that is to say "a doctrine orally received," that the speculative and philosophical or rather the theosophical doctrines of Israel are to be found. These are contained in two books, the _Sepher Yetzirah_ and the _Zohar_. The _Sepher Yetzirah_, or Book of the Creation, is described by Edersheim as "a monologue on the part of Abraham, in which, by the contemplation of all that is around him, he ultimately arrives at the conclusion of the unity of God"[19]; but since this process is accomplished by an arrangement of the Divine Emanations under the name of the Ten Sephiroths, and in the permutation of numerals and of the letters of the Hebrew alphabet, it would certainly convey no such idea--nor probably indeed any idea at all--to the mind uninitiated into Cabalistic systems. The Sepher Yetzirah is in fact admittedly a work of extraordinary obscurity[20] and almost certainly of extreme antiquity. Monsieur Paul Vulliaud, in his exhaustive work on the Cabala recently published,[21] says that its date has been placed as early as the sixth century before Christ and as late as the tenth century A.D., but that it is at any rate older than the Talmud is shown by the fact that in the Talmud the Rabbis are described as studying it for magical purposes.[22] The Sepher Yetzirah is also said to be the work referred to in the Koran under the name of the "Book of Abraham."[23]