Joel 2:1-3

Blow the trumpet in Zion, and sound the alarm on my holy mountain! Let all the inhabitants of the land tremble, for the day of Yahweh is coming —it is indeed near. A day of darkness and gloom, a day of cloud and thick darkness, like the dawn spreads on the mountains, a great and strong army! There has been nothing like it from old, and after it nothing will be again for generations to come. Before them a fire devours, and behind them a flame burns. Like the garden of Eden is the land before them, and after them it is like a desolate desert, and nothing can escape them.