Day

Boyd’s Bible Dictionary:

(shining). Natural Hebrew day from sunset to sunset (Gen. 1:55And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day. (Genesis 1:5); Ex. 12:1818In the first month, on the fourteenth day of the month at even, ye shall eat unleavened bread, until the one and twentieth day of the month at even. (Exodus 12:18)). Sabbath the only day named; others numbered (Lev. 23:3232It shall be unto you a sabbath of rest, and ye shall afflict your souls: in the ninth day of the month at even, from even unto even, shall ye celebrate your sabbath. (Leviticus 23:32)). Morning, noon, and evening divisions (Psa. 55:1717Evening, and morning, and at noon, will I pray, and cry aloud: and he shall hear my voice. (Psalm 55:17)). Hours introduced (Dan. 3:66And whoso falleth not down and worshippeth shall the same hour be cast into the midst of a burning fiery furnace. (Daniel 3:6); John 11:99Jesus answered, Are there not twelve hours in the day? If any man walk in the day, he stumbleth not, because he seeth the light of this world. (John 11:9)). Indefinite time (Gen. 2:44These are the generations of the heavens and of the earth when they were created, in the day that the Lord God made the earth and the heavens, (Genesis 2:4)); of birth (Job 3:11After this opened Job his mouth, and cursed his day. (Job 3:1)); of ruin (Hos. 1:1111Then shall the children of Judah and the children of Israel be gathered together, and appoint themselves one head, and they shall come up out of the land: for great shall be the day of Jezreel. (Hosea 1:11)); of judgment (Joel 1:1515Alas for the day! for the day of the Lord is at hand, and as a destruction from the Almighty shall it come. (Joel 1:15)); of Christ’s kingdom (John 8:5656Your father Abraham rejoiced to see my day: and he saw it, and was glad. (John 8:56)).

Concise Bible Dictionary:

Besides the ordinary application of the word, it is used in scripture as defining different periods. The term “that day” often occurs in the Prophets and in the New Testament referring to the Messiah’s day, sometimes connected with judgment and sometimes with blessing, the context of each passage showing its application. The subject generally may be divided into:
1. The days of the Law and the Prophets, which extended from the giving of the law until the coming of the Messiah. “At the end of these days [God] has spoken to us in [His] Son,” as Hebrews 1:22Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds; (Hebrews 1:2) should read. This introduced Messiah’s Day. But He was rejected and His reign postponed.
3. Messiah’s Day, when He returns in judgment and then to reign. “The day is at hand” (Rom. 13:1212The night is far spent, the day is at hand: let us therefore cast off the works of darkness, and let us put on the armor of light. (Romans 13:12); Heb. 10:2525Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching. (Hebrews 10:25)). “The day shall declare it” (1 Cor. 3:1313Every man's work shall be made manifest: for the day shall declare it, because it shall be revealed by fire; and the fire shall try every man's work of what sort it is. (1 Corinthians 3:13)). It is also called “the last day” (John 6:39-5439And this is the Father's will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day. 40And this is the will of him that sent me, that every one which seeth the Son, and believeth on him, may have everlasting life: and I will raise him up at the last day. 41The Jews then murmured at him, because he said, I am the bread which came down from heaven. 42And they said, Is not this Jesus, the son of Joseph, whose father and mother we know? how is it then that he saith, I came down from heaven? 43Jesus therefore answered and said unto them, Murmur not among yourselves. 44No man can come to me, except the Father which hath sent me draw him: and I will raise him up at the last day. 45It is written in the prophets, And they shall be all taught of God. Every man therefore that hath heard, and hath learned of the Father, cometh unto me. 46Not that any man hath seen the Father, save he which is of God, he hath seen the Father. 47Verily, verily, I say unto you, He that believeth on me hath everlasting life. 48I am that bread of life. 49Your fathers did eat manna in the wilderness, and are dead. 50This is the bread which cometh down from heaven, that a man may eat thereof, and not die. 51I am the living bread which came down from heaven: if any man eat of this bread, he shall live for ever: and the bread that I will give is my flesh, which I will give for the life of the world. 52The Jews therefore strove among themselves, saying, How can this man give us his flesh to eat? 53Then Jesus said unto them, Verily, verily, I say unto you, Except ye eat the flesh of the Son of man, and drink his blood, ye have no life in you. 54Whoso eateth my flesh, and drinketh my blood, hath eternal life; and I will raise him up at the last day. (John 6:39‑54); John 11:2424Martha saith unto him, I know that he shall rise again in the resurrection at the last day. (John 11:24); John 12:4848He that rejecteth me, and receiveth not my words, hath one that judgeth him: the word that I have spoken, the same shall judge him in the last day. (John 12:48)). And it is called “the great day.” Elijah will come before the great and dreadful day of the Lord (Mal. 4:55Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the Lord: (Malachi 4:5)). The kings of the earth will be gathered to the battle of that great day of God Almighty (Rev. 16:1414For they are the spirits of devils, working miracles, which go forth unto the kings of the earth and of the whole world, to gather them to the battle of that great day of God Almighty. (Revelation 16:14)). It is also called “the day of Christ” and “the day of Jesus Christ” (Phil. 1:6, 106Being confident of this very thing, that he which hath begun a good work in you will perform it until the day of Jesus Christ: (Philippians 1:6)
10That ye may approve things that are excellent; that ye may be sincere and without offence till the day of Christ; (Philippians 1:10)
; Phil. 2:1616Holding forth the word of life; that I may rejoice in the day of Christ, that I have not run in vain, neither labored in vain. (Philippians 2:16); compare 1 Cor. 1:88Who shall also confirm you unto the end, that ye may be blameless in the day of our Lord Jesus Christ. (1 Corinthians 1:8); 2 Cor. 1:1414As also ye have acknowledged us in part, that we are your rejoicing, even as ye also are ours in the day of the Lord Jesus. (2 Corinthians 1:14)).