This little book boils down to one thing: the rebuilding of the temple after Babylonian captivity.
The Lord really comes down on the people thru Haggai, His prophet, because they have been rebuilding their own homes, while neglecting His. He asks them to consider why all these bad things are happening to them, why their harvest is low, why they aren’t satisfied with their food and drink, etc. It’s like He’s saying, “Hey…yo…are you paying any attention? Can’t you figure out there’s a cause and effect relationship here?”
So, the Lord stirs up the leaders and the people to get to work. He promises He will be with them. And work on the temple continues, as we know from Ezra and Nehemiah. The people listen to the prophet’s message and act. This is good, because often times in biblical history, the Israelites do not listen to their prophets.
But before we get on our high horse and start criticizing them, let us look at our own hearts and our own nation and see if there’s a cause and effect relationship.
Sidenote: On two occasions, the Lord tells them He will shake the heavens and the earth. Why? I don’t know. I guess just to warn everybody.