What is the Genesis definition of "Day"?
Based on The Scroll of Biblical Chronology And Prophecy:
Mapping The Times And Seasons of The Holy Scriptures.
The Genesis definition of day is given in the fifth verse: "And God called the light Day, and the darkness he called Night" (Gen. 1:5). By this definition the "day" can mean no period of time longer than dawn to dusk. The text then defines the "night" as "darkness", which can only mean time from dusk to dawn. Further, the first day may or may not have had a dawn. If the newly created light increased gradually like turning up a dimmer switch on a lamp in a room, then the first day arguably has a dawn. If there was just a brilliant flash, then the first day has no dawn. Days two and beyond certainly had a dawn since the text speaks of "morning". Granting that a "dawn" for the first day is an assumption, I will assume it until proven otherwise simply to make the first day symmetrical to all the others.
We now have to deal with the next chronological statement in Genesis 1:5b. I give a literal translation directly from the Hebrew, "And there is setting, and there is morning". Why didn't I use the word "evening"? Because "evening" in English only means sunset to midnight. The Hebrew word is erev. Erev means setting and has been used for any time the light is perceived as setting or declining. The light begins to decline at noon. It sinks below the horizon at one point, and then at the end of dusk vanishes altogether. This period from noon to dusk is the longest definition of evening. Erev is also used specifically to mark the beginning of the decline (noon), and also when the light source vanishes (sunset after the 4th day). The end of dusk is not technically marked as a sense of erev.
Using this definition of erev, Israel later killed the Passover lamb "between the settings" (Exodus 12:6). This was the midpoint between noon and sunset, or between the point that the light began to decline and the point that the source disappears. Further proof of this can be found in my paper: When is the Passover supposed to be kept? This paper thoroughly proves that erev in Hebrew means the decline of the light. In the following chart, I illustrate the difference between the English "evening" and the Hebrew erev:
First the arrow on the first night is to show that this night was eternal darkness. Darkness was not crea
ted. It is simply the absence of light. In this universe, God began with totally dark empty space. Basically, it was a blank slate. There was no erev to mark any sort of start to this eternal darkness, because there was no light to decline. Furthermore, Genesis does not tell us how long there was between God's initial creation of the primordial water and the dawn of the first day. In Genesis, the duration of this period is undefined. (However, the Scripture reveals the duration of this period in Exodus 20:11 using a different definition of "day" pertaining to the Sabbath.) Further, Genesis One does not apply the "and there is setting, and there is morning" formula to the seventh day, as it transitions to the next chapter, where the Sabbath is introduced, nor is there any summary in Genesis that God created everything in six days, nor could there be, since day was defined as the "light" and God had created the primordial deep during the unbounded darkness before the first day.
Now we have to take account of the order of the phrase, "And there is setting, and there is morning, one day". And we do so in the next figure:
We cannot adopt the whole period of "morning" (boqer) as the meaning here (i.e. dawn to noon), but just the point when the light appears (or begins to appear), otherwise, there would have to be two days in the reckoning, the whole of the first day, and half of the second day. Hebrew counts inclusively. A part of a day is counted using the same language as a whole. In that respect, inclusive counting is ambiguous. So "morning" is this formula give the limit of the period, which is up to the point that the daylight lightens the earth. And by symmetry, "setting" or erev means the point at the end of the day when the light disappears.
Finally, the summation, "one day" does not mean the period between erev and boqer, which is clearly the night. We must view the erev and boqer as the limits marking off the night following the day, that must occur before the next day will begin. The proof that erev and boqer mark the boundaries of 12 hours of darkness after the day is in the realization that the order erev and boqer can never be 24 hours. After all morning (boqer) ends at noon by the most expansive definition. As pointed out above though, we cannot include a countable part of the second day, so boqer must be limited to the deep dawn. Erev need not be. It can extend back to noon and still only one day is counted, however symmetry suggests that it means only the point at which the light source disappears at the end of the day. So, "And it is erev, and it is boqer" simply mark the limits of the night at the end of each day.
When we get to the sixth day, the sixth day ends at sunset, and then the erev and boqer notation. As to 24 hour definitions of "day", Genesis leaves the matter open. It seems to suggest dawn to dawn as and extended definition of "day" by counting the day from the start of one day to the start of the next day, including the night after the day as part of one day. On the other hand, it is possible to count a 24 hour day from the end of one day to the end of the next day, in this case including the night before the day as part of the day. These 24 hour definitions of day, however require one to say "erev to erev" or "boqer to boqer", or to set "boqer" as the limit at the end of a day and "erev" as the limit of the start of a day. If boqer is set as a limit to end a day, then we go back to the preceding boqer to begin the day. Or if erev is set as a limit to start the day, then we must go to the next erev to end the day.
Strictly speaking, Genesis One only defines a day as the "light" and does not define a 24 hour "day". It leaves this matter of a legal definition open. And in fact, the Scripture employs both of the legal definitions, either sunset to sunset in the case of Sabbaths, or dawn to dawn to define a "day" for eating a sacrificial offering.
The development of the meaning of "day" started with Genesis 1:5, where God defined it as the "light". This is the default definition of day in a biblical context, and even the 24 hour definitions of a day pay some heed to it. (No one ever calls a "night" off by itself without some part of a day before or after it a "day".) In Genesis 2:4, "day" means a period of time that indicates 6 days. In Genesis 2:17, the word "day" means a period of time lasting one thousand years. So also with the "day of the LORD". Even in English we might say, "He was a strong man in his day", and the way we tell the difference between this idiomatic usage and the literal usage is simply context, the main rule being that if the first definition makes good sense, then it is the sense meant, otherwise look at the others.
Now the Egyptians adopted the sunrise to sunrise definition of a 24 hour day. The children of Israel in Egypt became thoroughly familiar with it, so when the Torah was given to Israel, if things are not explained in terms of a daylight day, then they are explained in terms of a dawn to dawn day. For instance, the instructions for the day of atonement are given in terms of the sunrise to sunrise day: "
"It shall be to you a sabbath of solemn rest, and you shall afflict your souls; on the ninth day of the month at setting, from setting to setting, you shall celebrate your sabbath" (Leviticus 23:32)
If the ninth day is dawn to dawn, then setting on the ninth day is unambiguously at sunset, right in the middle of the 24 hour period. This Sabbath will last until sunset on the 10th day of the month. In Lev. 25:9, the day of atonement is the 10th day of the month. In modern times, the notion that a "Jewish day" always begins and ends at sunset has led to some serious misunderstandings concerning the Passover. See may other paper: When is the Passover supposed to be kept?. However, nearly all of the Passover legislation is given from the standpoint of the dawn to dawn day that Israel used in Egypt. Only in the respect of holy days that are Sabbaths are matters given differently, yet even the day of atonement uses the dawn to dawn day to describe how to keep it.
When the tabernacle and the Temple stood, the end of "the same day" for the purpose of eating "peace offerings" was "until the morning" (Leviticus 7:15). This was the dawn to dawn day wherein the night following a day was made part of the 24 hour period. The real exception to the dawn to dusk day and the dawn to dawn day was the reckoning of the Sabbaths. A similar departure also occurs with the seventh year and the Jubilee year from the beginning of the natural year. They begin in the fall, with the 7th month. The purpose was to set sacred time apart from common time. The sacred day was given a 12 hour buffer of night to include before the day as part of the legal 24 hour definition, and the sacred year was defined to begin in the fall to make it agree with the agricultural cycle.
Exodus 20:11 tells us that God created everything in "six days". Since the Sabbath was in view, this comprehensive statement is made with a view to including the night or darkness before the day as part of the 24 hour definition of "day". For this reason, the text reveals that the primordial waters and empty earth were made not more than 12 hours before God said, "Let there be light".
So in biblical times, the dawn to dawn and dusk to dusk definitions of day existed right alongside the dawn to dusk definitions and the "period of time" definitions. However, after the destruction of the second temple, and the cessation of the Levitical sacrifices the dawn to dawn day faded into the background, and that Sabbath element of Torah that the Jews could observe in exile was emphasized, namely weekly Sabbaths and festival Sabbaths. These days, of course, were always erev to erev like the day of atonement. So the dawn to dawn day fell into obscurity.
It is therefore with the greatest of ignorance that anyone insists that the "Genesis day" always begins with sunset. Some persons detect this ignorance and tell us that the Sabbath is to be kept from sunrise to sunrise, or just dawn to dusk. These people are also ignorant, and are ignoring the collective memory of the Jewish people. What is most interesting however, is that while Jews tend to keep the correct times for observances, they do not always have the correct explanations for why they are following the tradition. A lot of this has to do with Yeshua of Nazareth's death and resurrection. Certain Rabbis would rather that the Jewish people forget certain precise teachings of Torah lest those institutions be seen to be fulfilled by the "Christian" Messiah. Yet Yeshua is really the Jewish Messiah, and with respect to the meaning of a "day", his death and resurrection is in terms of all the various definitions! For this you can see my article: The Sabbath Resurrection. Meanwhile, I leave you with the chart:
