When period does the 'day of the Lord' refer to?

Hi!

thanks for the question. It is a good question though it can be a tricky subject! The timing, nature and length of the 'day of the Lord' are certainly debated among Christians interested in prophecy. And it is a subject that requires a good overview of various passages throughout the entire Bible for it is mentioned throughout the prophets as well as the New Testament references. A book that helped my understanding on this topic is Renald Showers 'Maranatha'. It is a book on the rapture but goes into the timing and nature of the day of the Lord in some detail.

Anyway, here are some thoughts to hopefully help with your questions. To be honest it is a BIG topic and hard to do justice with some quick points... But I'll try! A lot of my answer will be based on that which I have learned from Renald Showers' book.

Firstly some definitions and background... The reason why people get confused on the day of the Lord is because sometimes it is speaking of the entire 7 year tribulation period (and the following Messianic Kingdom) and sometimes it is speaking of a specific actual day - with that day being the day of the Lord's return at the end of the tribulation. Showers speaks of this as the 'broad' and 'narrow' day of the Lord. This is consistent with the earliest use of the word 'day':

Gen 1:5 God called the light "day," and the darkness he called "night." And there was evening, and there was morning--the first day.

You will see here that 'day' can apply in a narrow sense to the period of light. It can also apply to the entire 'day' which includes darkness (evening, first) and light (morning, second). The 'day of the Lord' at the end of the age also has a broad and narrow sense. The broad day includes all of the last 7 year tribulation and the Messianic Kingdom - just as a day in Jewish thought, based on the Genesis 1 account, had night first (the darkness of the tribulation) and then the light of day (the coming Kingdom age). The narrow day is the return of Jesus to the earth as King of Kings. So for example, often the day of the Lord is equated with the 'birth pangs' of the Messiah (Isa 13:6-13, 1 Thes 5:2-3) The birth pangs go throughout the last 7 year period with the first half of this period being referenced by Jesus as the 'beginning of birth pangs' (Matthew 24:8) The birth pangs increase in strength and frequency throughout 'Daniel's 70th week' leading up to Jesus return. So this speaks of the day of the Lord as an extended period covering the entire duration of God's judgement and then blessing of this planet. 

On the other hand, the 'narrow' day of the Lord is specifically talking about the day of Jesus' return. That is why it can say that Elijah (who most believe is one of the two witnesses during the tribulation) must come BEFORE the great and terrible day of the Lord - this is a reference to the final narrow day of Jesus return. It is also why Joel could say that when all the nations are in the valley of Jehoshaphat for judgement, 'the day of the Lord is at hand'! This has confused people because everyone knows this even happens right at the end of the tribulation - so the only way that the 'day of the Lord' could still be future at this point is if it is speaking specifically of the actual second coming of the Lord.

Joel 3:12-14 Let the nations be aroused And come up to the valley of Jehoshaphat, For there I will sit to judge All the surrounding nations. (13) Put in the sickle, for the harvest is ripe. Come, tread, for the wine press is full; The vats overflow, for their wickedness is great. (14) Multitudes, multitudes in the valley of decision! For the day of the LORD is near in the valley of decision.

As a side note, I believe that the references to the 'great and terrible/awesome' day of the Lord are specifically looking at the second coming of Jesus and not the entire 7 year tribulation period.

Mal 4:5 "Behold, I am going to send you Elijah the prophet before the coming of the great and terrible day of the LORD.

Joe 2:31 "The sun will be turned into darkness And the moon into blood Before the great and awesome day of the LORD comes.

Joe 2:11 The LORD utters His voice before His army; Surely His camp is very great, For strong is he who carries out His word. The day of the LORD is indeed great and very awesome, And who can endure it?

Right... Still with me? : ) With that as a background onto your questions.

What is the day of the Lord a reference to in 1 Thes 5?

1 Thessalonians 5:1-5 Now as to the times and the epochs, brethren, you have no need of anything to be written to you. (2) For you yourselves know full well that the day of the Lord will come just like a thief in the night. (3) 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. (4) But you, brethren, are not in darkness, that the day would overtake you like a thief; (5) for you are all sons of light and sons of day. We are not of night nor of darkness;

This passage tells us that the day of the Lord will come when people are sayin 'peace and safety'. It also links it to the birth pains coming suddenly. This is a reference to the 'broad' day of the Lord which include the start and all of the birth pangs - the entire 7 year period. It doesn't make sense being anything else. At no point during the final 7 year period will people be saying 'peace and safety'. It doesn't make sense trying to apply this day of the Lord to the return of Jesus at the end of the seven years as that is when judgments are poured out and will not be a time of peace and safety. It makes sense BEFORE the tribulation begins. Leading up to this last 7 year period the Antichrist will be assuming control and will make a peace treaty for 7 years with Israel. Finally, it will seem like the previously completely elusive Middle East peace has been achieved. People will be saying peace and safely! And then the day of the Lord with judgement from on high will begin for that final 7 year period.

What is the day of the Lord in 2nd Thes 2 referring to?

2 Thessalonians 2:1-2 Now we request you, brethren, with regard to the coming of our Lord Jesus Christ and our gathering together to Him, (2) that you not be quickly shaken from your composure or be disturbed either by a spirit or a message or a letter as if from us, to the effect that the day of the Lord has come.

It is the same period as mentioned above in 1 Thes 5. Two things come before it - the departure or apostasy from the faith (some believe this is actually 'the departure' and is a reference to the rapture) and the Antichrist, the man of sin, will be revealed. So when is the man of sin revealed? Some say at the mid point of the tribulation when he puts himself in the temple and declares himself to be God. But as Showers points out, there are problems with this because God puts lots of things in scripture that will identify this coming leader well before that point. Namely, he will rise as the 11th ruler in a 10 division conference (Dan 7:7-8, 23-24), he will overthrow 3 of the original 10 kings (Dan 7:8, 20,24), he will become the dominant leader of the revised Roman Empire (Dan 7:20, 24, 26, Rev 17:12-13, 16-17). And finally he will confirm a 7 year covenant with Israel (Dan 9:27). So it is fair to assume that people will be able to know who the Antichrist is by the signing of the 7 year covenant.

The problem in 2 Thess 2 is that the believers were being told that they were actually in the day of the Lord. This was contrary to what Paul had previously taught them and was freaking them out! They were 'quickly shaken' and 'disturbed' as Paul wrote about. So Paul was saying that the day of the Lord won't come until there is a great apostasy (or possibly the departure/rapture) and the coming of the Antichrist. And note also that the Antichrist can't be revealed until the restrainer, who is the Holy Spirit, is removed. This means that the Church, indwelt with the Holy Spirit, is not going to see Antichrist.

See also
https://www.jashow.org/articles/prophecy/how-and-when-will-the-man-of-sin-be-revealed-2-thess-23/

https://bible.org/seriespage/chapter-8-revelation-man-sin

One last thing to bear in mind in regards to your question is that the references to the 'day of the Lord' are not talking about the rapture. It is talking, in this context, of that period of God's judgement upon the earth (and then His blessing in the Kingdom). So 2 Thes 2 is not saying that the revelation of the Antichrist and the Apostasy have to happen before the rapture, only that they happen before the day of the Lord. And, as 1 Thes 5 tells us, we are not of that day of darkness (1 Thes 5:4-5) nor will we see God's wrath (1 Thes 1:10, 5:9).

Hope this helps. Like I said, it's a big topic! : )

God Bless