The day is distinguished into natural, civil, and artificial. The natural day is one revolution of the earth on its axis. The civil day is that, the beginning and the end of which are determined by the custom of any nation. The Hebrews began their day in the evening, Leviticus 23:32; the Babylonians at sunrise; and we begin at midnight. The artificial day is the time of the sun’s continuance above the horizon, which is unequal according to different seasons, on account of the obliquity of the equator. The sacred writers generally divide the day into twelve hours. The sixth hour always ends at noon throughout the year; and the twelfth hour is the last hour before sunset. But in summer, all the hours of the day were longer than in winter, while those of night were shorter. See HOURS, and THREE.

The word day is also often put for an indeterminate period, for the time of Christ’s coming in the flesh, and of his second coming to judgment, Isaiah 2:12 Ezekiel 13:5 John 11:24 1 Thessalonians 5:2. The prophetic "day" usually is to be understood as one year, and the prophetic "year" or "time" as 360 days, Ezekiel 4:6. Compare the three and half years of Daniel 7:25, with the forty-two months and twelve hundred and sixty days of Revelation 11:2,3.

The Jews reckoned the day from sunset to sunset (Leviticus 23:32). It was originally divided into three parts (Psalms 55:17). "The heat of the day" (1 Samuel 11:11; Nehemiah 7:3) was at our nine o'clock, and "the cool of the day" just before sunset (Genesis 3:8). Before the Captivity the Jews divided the night into three watches, (1) from sunset to midnight (Lamentations 2:19); (2) from midnight till the cock-crowing (Judges 7:19); and (3) from the cock-crowing till sunrise (Exodus 14:24). In the New Testament the division of the Greeks and Romans into four watches was adopted (Mark 13:35). (See WATCHES .)

The division of the day by hours is first mentioned in Daniel 3:6,15; 4:19; 5:5. This mode of reckoning was borrowed from the Chaldeans. The reckoning of twelve hours was from sunrise to sunset, and accordingly the hours were of variable length (John 11:9).

The word "day" sometimes signifies an indefinite time (Genesis 2:4; Isaiah 22:5; Hebrews 3:8, etc.). In Job 3:1 it denotes a birthday, and in Isaiah 2:12, Acts 17:31, and 2 Timothy 1:18, the great day of final judgment.

DAY, n.

The variable length of the natural day at different seasons led in the very earliest times to the adoption of the civil day (or one revolution of the sun) as a standard of time. The Hebrews reckoned the day from evening to evening, (Leviticus 23:32) deriving it from (Genesis 1:5) "the evening and the morning were the first day." The Jews are supposed, like the modern Arabs, to have adopted from an early period minute specifications of the parts of the natural day. Roughly, indeed, they were content to divide it into "morning, evening and noonday," (Psalms 55:17) but when they wished for greater accuracy they pointed to six unequal parts, each of which was again subdivided. These are held to have been -- "the dawn." "Sunrise." "Heat of the day," about 9 o’clock. "The two noons," (Genesis 43:16; 28:29) "The cool (lit. wind ) of the day," before sunset, (Genesis 3:8) --so called by the Persians to this day. "Evening." Before the captivity the Jews divided the night into three watches, (Psalms 63:6; 90:4) viz. the first watch, lasting till midnight, (Lamentations 2:19) the "middle watch," lasting till cockcrow, (Judges 7:19) and the "morning watch," lasting till sunrise. (Exodus 14:24) In the New Testament we have allusions to four watches, a division borrowed from the Greeks and Romans. These were -- From twilight till 9 o/clock, (Mark 11:11; John 20:19) Midnight, from 9 till 12 o’clock, (Mark 13:35) 3 Macc 5:23. Till daybreak. (John 18:28) The word held to mean "hour" is first found in (Daniel 3:6,15; 5:5) Perhaps the Jews, like the Greeks, learned from the Babylonians the division of the day into twelve parts. In our Lord’s time the division was common. (John 11:9)