5 Declare ye in Judah, and publish in Jerusalem; and say, Blow ye the trumpet in the land: cry, gather together, and say, Assemble yourselves, and let us go into the defenced cities.
When an alarm was blown it portended great evil. See also Joel 2:1... When an alarm was blown it portended great evil.
6 Set up the standard toward Zion: retire, stay not: for I will bring evil from the north, and a great destruction.
The beasts being substituted for the metals represent of course the same dominions. The lion was a very appropriate symbol for the Assyrian dynasty; and it was as well understood to represent it in the days of the prophets, as it is now that the lion and unicorn are symbols of the British power. Hence, speaking of the overthrow coming upon Judah by Nebuchadnezzar, Jeremiah says...
7 The lion [of Babylon] is come up from his thicket, and the destroyer of the Gentiles is on his way; he is gone forth from his place to make thy land desolate; and thy cities shall be laid waste, without an inhabitant.
13 Behold, he shall come up as clouds, and his chariots shall be as a whirlwind: his horses are swifter than eagles. Woe unto us! for we are spoiled.
Clouds - a multitude: Whirlwind - rushing and ferocious, demolishing everything in its path. No escape from the coming wrath for those who remained.
As a horse is warlike, so he is also a swift creature, and is therefore not only the symbol of conquest, but also of the speediness of it
14 O Jerusalem, wash thine heart from wickedness, that thou mayest be saved. How long shall thy vain thoughts lodge within thee?
The choice is ours - cleanse ourselves of sin and be saved, or indulge the pleasures of sin for a season and perish.