The [e]proud look of man will be abased
And the loftiness of man will be humbled,
And the Lord alone will be exalted in that day.
For the Lord of hosts will have a day of reckoning
Against everyone who is proud and lofty
And against everyone who is lifted up,
That he may be abased. (Isaiah 2:11-12 NASB)
The purpose of this great day of judgment, which we refer to as “The Day Of The Lord” is to abolish the arrogance and pride of man and humiliate him in the presence of the one true God who alone deserves worship and honor. We all need to repent from the “proud look” and give glory to God now, before he comes and makes us do it by force! God’s glory in that day will be irresistible. He will show the human race how weak and contemptible we really are.
So when does the day of the Lord come? I believe this day of the Lord happens during the tribulation period. It could be a reference to the entire tribulation period, or perhaps just to the tail end. I personally think that it refers to the entire tribulation because it will come without warning upon the unbelievers, like a “thief in the night” (I Thessalonians 5:2). Passages from the Book of Revelations that seem to correspond with descriptions of the day of the Lord are the 6th seal (Revelation 6:12-17) and the seventh Bowl (Revelation 16:17-21).