And it shall come to pass in that day, that the mountains shall drop down new wine, and the hills shall flow with milk, and all the water-courses of Judah shall flow with waters; and a fountain shall come forth from the house of Jehovah, and shall water the valley of Shittim.
Joel 3:16 And Jehovah will roar from Zion, and utter his voice from Jerusalem; and the heavens and the earth shall shake: and Jehovah will be a shelter for his people, and the refuge of the children of Israel.
Joel 3:17 And ye shall know that I, Jehovah, [am] your God, dwelling in Zion, my holy mountain; and Jerusalem shall be holy, and no strangers shall pass through her any more.
Joel 3:18 And it shall come to pass in that day, that the mountains shall drop down new wine, and the hills shall flow with milk, and all the water-courses of Judah shall flow with waters; and a fountain shall come forth from the house of Jehovah, and shall water the valley of Shittim.
Joel 3:19 Egypt shall be a desolation, and Edom shall be a desolate wilderness, for the violence against the children of Judah, in that they have shed innocent blood in their land.
Joel 3:20 But Judah shall abide for ever, and Jerusalem from generation to generation.
The verse centers on "shall", "come", "pass", "mountains", "drop", "down", and "wine". It is saying that the verse draws attention to "shall" and "come", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 17's "And ye shall know that I Jehovah..." into verse 19's "Egypt shall be a desolation and Edom...", so "shall" and "come" belong inside that flow. In Joel context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "shall" and "come" with trust shaped by these words, not by a vague optimism outside the passage.