Oracles introduced by "alas" ("woe oracles") have a particular shape to them, usually - as here - using participles to describe/identify the persons addressed.
Though these verses are the only explicit reference to "Adonai's Day" in the book, there are other phrases concerning a particular "day".
Here Amos assumes to a certain degree a shared world with his hearers. Both know of Adonai's Day, neither deny it, or apparently disagree about its context and content (as modern scholars do), however the prophet denies that his hearers ought to desire this "day".
The book of Amos, and the language of this passage suggest that this "day" is a time when Adonai will "intervene" decisively (compare particularly ch 4:6-13 and on the use of language see Andersen & Freedman 521). Like the person who, fleeing a lion meets a bear and reaching the "safety" of home is bitten by a snake (v.19), Amos claims Adonai's Day will mean disaster not salvation for Israel. It is "darkness" not "light".
The antithesis of "darkness" and "light" is commonly used in the Bible to suggest others like good and evil, safety and danger, hiddenness and openness. Here it reminds us of the interchange of dark and light in the hymnic fragments.
"Gloom" and "no brightness" speak of a particularly threatening kind of "darkness".
This page is part of the Hypertext Bible Commentary - Amos,
© Tim Bulkeley, 1996-2005, Tim Bulkeley. All rights reserved.