Book of the Luminary: On the Hours of the Day

When R. Dara arrived, he said: It is necessary that there be [both] night and day of the [new] month. [b. Rosh Hashanah 20b]

Herein lie three legal traditions, profound in their depth and difficult to interpret. They are inscrutable and incomprehensible to the mind of most scholars, who determined, in their view, that they are unacceptable as matters of standard Jewish law. This is surprising. How can all the discussion recorded in the Talmud concerning intercalation [i.e., the rules determining the Jewish calendar] be inconsistent with Jewish law? How should we rely upon the treatises composed on the secret of intercalation, and reject the authority of the Talmud? I therefore assert that all these legal traditions are stated in accordance with Jewish law. Their words form the foundation of the secret of intercalation handed down by tradition. However, the meaning is remote from our knowledge: [That which exists is far off] and exceeding deep; who can find it out? (Ecclesiastes 7:24). Now, I assert—as one who declares himself the greatest ignoramus of all, possessed of no human understanding, having learned nothing, yet presuming to know the knowledge of holy things, and whom the Jewish scholars of Spain practically banished in their wisdom—nevertheless, I deign to write my opinion in [the matter of] these legal traditions. I deem it proper to preface for you premises that will serve as the foundation and pillars by which to support the hidden secrets alluded to by the ways of wisdom regarding these legal traditions.

Know that the times of day and night are not simultaneous in all inhabited regions, nor on the earth in general. For in each twenty-four-hour period of the day and night, across the length of the earth, any given hour is evening in one place but morning in another in every longitude. This is in accordance with the circuit of the sphere [of the heavens] across it, which revolves from east to west. This is what is meant by: And there was evening and there was morning (e.g., Genesis 1:5) in the story of creation. Now, on the line circuiting the circumference of the earth over the fourth zone of the seven climes, which is the middle of the inhabited globe, there are four points corresponding to the four quarters of the day, which are: the beginning of the day, the beginning of the night, midday, and midnight. These four quarters of the day correspond to the temperaments, between humidity and dryness, and between heat and cold, which mirror the four seasons of the year. Now, the four points in the line circuiting the diameter of the earth [consist of the following]: the first is the end of the east; its inhabitants are those who dwell on the shores of the great ocean in the east. The second point is opposite the first; it is the end of the west; its inhabitants also dwell on the shores of the great ocean in the west. The third point is intermediary between these first two points on the surface of the earth. It is called the hub [umbilicus] of the earth. Its inhabitants are those who dwell in Jerusalem and all the land of Israel. The fourth point, opposite it, is under the earth. It also is intermediary between the first two points. It is called the hub [or umbilicus] of the sea, or the heart of the sea, or “the point of the abyss.”

Now, between each of these four points and the point opposite it is a distance of twelve hours longitude in accordance with the circuit of the sphere across them. And from each point to the next, a distance of six hours longitude exists in accordance with the circuit of the sphere across them. To illustrate this, when it is morning for the inhabitants of the east, it will not be morning for the inhabitants of Jerusalem until six hours later. You should calculate in a similar fashion for each hour the distance from each of the four points to the point adjacent it; this is the passage of the sun in the circuit of the [celestial] sphere each twenty-four hours over these four points.

Know that the reckoning of the days counted as the days of the week commences from the third point, which is the hub of the earth, that is, the land of Israel. To illustrate this, when the first day of the week begins for the inhabitants of Jerusalem, it will not begin for the inhabitants of the end of the west for another six hours. [ . . . ]

So, it has been made clear to you from this that there is a discrepancy of eighteen hours for the reckoning of the days and hours of the week between the inhabitants of Jerusalem and the inhabitants of the end of the east. For the inhabitants of Jerusalem are in advance of the inhabitants of the end of the east, even though the passage of the great luminary [i.e., the sun] across the [expanse of the] east is but six hours when you start counting from the end of the east. But with regard to the counting of the days of the week and [the reckoning of] their hours, thus is their order. And this order has been arranged for them since the six days of creation. Thus is the distance between them, according to the passage of the great luminary, as you commence to calculate from the land of Israel.

Know that the basis of the mystery for calculating the leap year, as passed down to us [by tradition], lies firmly in mighty mountains of holiness; they are two points of the four [points] mentioned [above]. One is the land of Israel. For it is holy ground, in which lies the holy city [of Jerusalem]. It is the place wherein the Lord chose to establish His name, as it says concerning this: there you shall come (Deuteronomy 12:5). The second is the end of the east, [which is] the dawn of civilization, in accordance with the words of the prophet: And, behold, the glory of the God of Israel came from the way of the east; and His voice was like the sound of many waters; and the earth did shine with His glory (Ezekiel 43:2). This means that the calculation of the new moon, which we say occurs on such-and-such a day, at such-and-such an hour of the day or of the night, is relative to Jerusalem. [ . . . ]

Know that the moon has no radiance of its own, only light emanated upon it from the light of the sun. The new moon [molad] consists in the conjunction of the moon [and the sun] in a single part of their celestial spheres. This conjunction is as the wink of an eye, [whereupon] they immediately detach from each other. The moon then continues to distance itself from the sun toward the east. The light of the sun increasingly spreads over the surface of the moon visible to the earth, according to its distance: Murmur by murmur, now here, now there (Isaiah 28:10, 13). But this is invisible to the eye until the distance reaches twelve degrees, per the degrees of the firmament, that is, three hundred and sixty degrees of the entire firmament. This is the excess [motion] of the moon’s course over [the course of] the sun every twenty-four hours. Thus, the light [of the sun] diffuses over its surface until it becomes apparent to the eye, which perceives it before the setting of the light of the sun. This is the onset of the crescent moon when it is new. It is seen to the west. The opposite of this [is true] for the old [waning] moon is seen in the eastern quadrant at its thinnest at the time of sunrise. This is as the measure of the distance mentioned [above], that is, twelve degrees. It immediately proceeds to approach the sun, when it is concealed [from view] by its [the sun’s] light until it returns, and again conjoins with it as before. In this way, it returns and completes its circuit.