Joel is all about the Day of the Lord.
Chapter 1 is twenty verses of devastation in the land of Israel. He starts off saying,
(v. 2) Has anything like this ever happened in your days or in the days of your ancestors?
The implied answer is, "No!"
It will be a story worth telling to their children, their grandchildren, and even their great grandchildren.
(1:15 and 2:11) Alas for that Day! For the Day of the Lord is near; it will come like destruction from the Almighty. ... The Day of the Lord is great; it is dreadful. Who can endure it?
Who can endure it? In Matthew 4:21-22 and Mark 13:19-20 Jesus tells us that if God had not shortened the days (to only 7 years?) then "no flesh" would survive. Because this Day will be ultimately destructive to our Earth (see Revelation).
(v. 10) Before them the Earth shakes, the Heavens tremble, the Sun and Moon are darkened, and the Stars no longer shine.
(v. 31) The Sun will be turned to darkness and the Moon to blood before the coming of the great and dreadful Day of the Lord.
(3:15) The Sun and Moon will be darkened, and the Stars no longer shine.
Revelation 6:12-13, 8:12, Matthew 24:29, Mark 13:24-25 and Luke 21:25 all talk about these same astronautical phenomenons of observable changes in the Sun, Moon and Stars, immediately preceding the Glorious Appearing.
Chapter 2 talks about God's mighty locust army that,
(v. 4) have the appearance of horses.
So they're locusts that look like horses; Revelation talks about this same thing, with much more description of them in chapter 9, verses 7 to 10.
Then right in the middle of all this gloom-and-doom, Joel says that there's still an opportunity to not be among those who are judged. He says,
(2:12-14) "Even now," declares the Lord, "return to Me with all your heart, with fasting and weeping and mourning." Rend your heart and not your garments. Return to the Lord your God, for He is gracious and compassionate, slow to anger and abounding in love, and He relents from sending calamity. Who knows? He may turn and relent and leave behind a blessing--grain offerings and drink offerings for the Lord your God.
Even though Joel is pronouncing God's judgments on Judah and Israel, there is still room for them to change their minds and decide to do things God's way. And He just might turn the planned judgment into a blessing!
Then the following passage (vs. 15-27) describes all the blessings God will shower upon His people when they do turn around their attitudes and actions, and God even says that,
(v. 25) "I will repay you for the years the locusts have eaten."
This is a promise for all of God's people, not just for the Hebrews. As Christians today, we can claim this promise, and expect our Heavenly Father to restore what our own foolish choices have lost us, when we also turn our own attitudes and thinking processes around from the World's ways to align with God's ways for us.
Now in chapter 3 Joel talks quite a bit on what we refer to as the "Battle of Armageddon" (from Revelation 16:16), calling the place the Valley of Jehoshaphat (vs. 2, 12) and the Valley of Decision (twice in v. 14), as a judgment of the Nations for their treatment of Israel and the Jews, to
(3:2) put them on trial for what they did to My inheritance, My people Israel, and
(3:19) because of violence done to the people of Judah.
In Matthew 25:31-40 Jesus says that when the Son of Man comes in His glory with His holy ones, He will sit on His throne of glory and judge the Nations, according to how they treated, "the least of these, My brethren" (v. 40).
We are those Nations, the individuals who choose our leaders with our votes, or allow them to rule us through not bothering to vote or voice our views. We are responsible to be on the side of God's people Israel, as they are again a Nation among the Nations of the World, and to help those who are still dispersed to meet their material and spiritual needs, or to even do what we can to help them make aliyah back home to their ancient land of Israel.
This little 3-chapter book is so densely filled with meaning, I don't think I've even scratched the surface of it's depth.
If you have further thoughts on any of this, I welcome your comments, and will consider your views.
Even so, come, Lord Jesus!
