In my article, Jesus’ Divinity Within Jewish Monotheism, I discussed the many New Testament scriptures which indicated the early Christian belief that Jesus was divine. While reading I. Howard Marshall’s fine commentary on 1 and 2 Thessalonians, I became aware of more such evidence. The relevant passage is 1 Thessalonians 5:1-6:
Now as to the times and the epochs, brethren, you have no need of anything to be written to you. For you yourselves know full well that the day of the Lord will come just like a thief in the night. While they are saying, "Peace and safety!" then destruction will come upon them suddenly like labor pains upon a woman with child, and they will not escape. But you, brethren, are not in darkness, that the day would overtake you like a thief; for you are all sons of light and sons of day. We are not of night nor of darkness; so then let us not sleep as others do, but let us be alert and sober.
According to Marshall,
“[T]he day of the Lord is an OT phrase which, whatever its origins, had come to be used to signify that future date on which God would act in power to establish his will. It is above all the day of his judgment; but it also brings salvation. It was taken over in NT use to refer broadly to the time of the End.... The early church naturally understood the "Lord" in the OT phrase to be Jesus.”
Marshall, 1 and 2 Thessalonians, A Commentary, page 133.
Examples of such Old Testament references to the "day of the Lord" are:
Alas, you who are longing for the day of the Lord, for what purpose will the day of the Lord be to you? It will be darkness and not light; as when a man flees from a lion and a bear meets him, or goes home, leans his hand against the wall And a snake bites him. Will not the day of the Lord be darkness instead of light, even gloom with no brightness in it?
Wail, for the day of the Lord is near! It will come as destruction from the Almighty. Therefore all hands will fall limp, And every man's heart will melt. They will be terrified, Pains and anguish will take hold of them; they will writhe like a woman in labor, they will look at one another in astonishment, their faces aflame. Behold, the day of the Lord is coming… And the earth will be shaken from its place at the fury of the Lord of hosts In the day of His burning anger.
Alas for the day! For the day of the Lord is near, and it will come as destruction from the Almighty. Has not food been cut off before our eyes, gladness and joy from the house of our God?
See also Obadiah 1:15-21 and Zephaniah 1:14-16.
From these Old Testament passages, we can see that the reference to the “day of the Lord” is a time of Judgment from God. There is no ambiguity about the identity of “the Lord”; it is God. The Day of the Lord is the Judgment Time of God.
As Marshall discusses above, this OT usage was adopted in the New Testament. It still refers to the time of judgement, but identifies the Lord of that Day with Jesus. Beyond the terminology, Jesus is seen as filling the role of God on that day. This puts Jesus in a place of very high Christology.
Probably the most explicit text from the Gospels is Luke 17:24:
"For just like the lightning, when it flashes out of one part of the sky, shines to the other part of the sky, so will the Son of Man be in His day.”
From Matthew, there are passages identifying Jesus with the time of judgment (Matthew 24:37 and Matthew 24:39).
And in Paul’s letters, in addition to the verses from Thessalonians discussed above, the connection is repeated in 1 Corinthians and Philippians;
“[W]ho will also confirm you to the end, blameless in the day of our Lord Jesus Christ.”
1 Corinthians 1:8.
“I have decided to deliver such a one to Satan for the destruction of his flesh, so that his spirit may be saved in the day of the Lord Jesus. “
1 Corinthians 5:5.
“For I am confident of this very thing, that He who began a good work in you will perfect it until the day of Christ Jesus.”
“[H]olding fast the word of life, so that in the day of Christ I will have reason to glory because I did not run in vain nor toil in vain.”