they do not divide themselves into symmetrical groups of days. Here the numerical scheme has been at work, and this cannot be referred to the phases, since these give no other naturally grounded divisions than the halves of the month. The derivation of the Israelitish sabbath from Babylonia therefore offers two difficulties:--1, in regard to the word, Babylonian _shabattu_ means the day of full moon, in fact the fifteenth day of the lunar month, and Hebrew _shabbat_, so far as we know, the seventh day of a period that is shifting in relation to the lunar month; 2, in regard to the period of time, in Babylonia the septenary scheme is a fixed division of the lunar month; among the Israelites it is, so far as we know, shifting, continuous, and independent of the lunar month. I have emphasised the phrase ‘so far as we know’ since in reality our sole knowledge in this direction of the Israelitish times before the Exile is that a festival and rest-day called the sabbath existed: of its nature we know nothing. The earliest evidence we have of it is the story of one of the miracles of Elisha[1112], from which it appears that the adherents of the prophet were accustomed to gather round him on this day and at new moon, doubtless since both were rest-days. In the same way sabbath and new moon are mentioned together as festival days in Amos VIII, 5, Hosea II, 11, Isaiah I, 13. The writers during and after the Exile are the first to mention the sabbath as the seventh day of a continuous seven-day week. It has at that time the character of an ascetic rest-day, where the rest is not a joy but a duty.