Shall not. ? Figure of speech Erotesis (App-6), for emphasis
and no brightness. Note the Figures of speech Pleonasm and Erotesis (App-6). Some codices omit "and".
Related Commentaries of Amos 5:20
Amos 5:20
20 Shall not the day of the LORD be darkness, and not light? even very dark, and no brightness in it?