Evening ends the daylight portion.
Morning ends the night.
One day is complete.
"There was an evening and there was a morning...one day"
You can't have evening without light...it went from eternal darkness to "Light!" and then the evening came...then the morning...one day
Google it up..."when does the biblical day begin"etc.
Here's a good intro...
Here is some historical evidence that supports the Biblical Truism that a day begins at sunrise: “Meaning of “day”: In the Bible, the season of light (Gen. 1:5), lasting from dawn (literally “the rising of the morning”) to the coming forth of the stars” (Jewish Encyclopedia, page 475)
“In order to assure against profanation of the Sabbath the Jews added the late Friday afternoon hours to the Sabbath” (The Jewish Festivals: History & Observance, p.13).
[Note: The Jews changed the configuration of a day and added the time between sunset and sunrise to the day. This is not Biblical but constitutes a pharisaical approach!]
“If we look at the essentials of a day of rest and reflection which has a religious orientation, it is possible to justify the shifting of Sabbath worship to Friday evening, the celebration of the vigil/night watch was moved back to the eve of the Feast as early as the middle ages…” (Judaism: Between Yesterday and Tomorrow, p. 518).
“…a sacred day of rest on the 7th day (the Sabbath). Days were reckoned from morning to morning…” (New Catholic Encyclopedia, Vol. 11, pg. 1068).
“Following the reign of King Josiah (c. 640-609), and especially after the Babylonian exile, a number of significant and enduring changes occurred in the Israelite calendar showing that the Jews gradually adopted the Babylonian calendar of the time…The day however, was counted from evening to evening, after the Babylonian fashion….” (New Catholic Encyclopedia, Vol. 11, section titled “Later Jewish Calendar”).
“…shortly after the beginning of the Greek period, [236 BC] came the change in the method of reckoning the day, from evening to evening instead of from morning to morning as of old…” (The Calendars of Ancient Israel, p. 146)
http://christianitybeliefs.org/the-...-that-prove-that-a-day-starts-in-the-morning/
Keep in mind Sunday keepers need the sundown to be start of next day...as biblical days beginning in the morning destroys Sunday resurrection as all that was discovered that morning was an empty tomb...He was risen the day/night before. They can't argue..."but but but Sunday started before dawn"
A powerful example of good (evidence for timing of biblical days) coming from evil...
"So they made their father drink wine that night. And the first-born went in and lay with her father, and he was not aware of it when she lay down or when she arose. And it came to be on the next day that the first-born said to the younger, “See, I lay with my father last night. Let us make him drink wine tonight as well, and you go in and lie with him, so that we keep the seed of our father” ” (Gen. 19:33-34).