One day. — i.e., an extraordinary, unique day. (Comp. Ezekiel 7:5.) “An evil, an only (literally, one) evil, behold, is come.” (Also Jeremiah 30:7.)
Not day, nor night. — But a kind of murky gloom, such as accompanies a sand-storm in the deserts of the East.
It shall be. — Better, there shall be. As the darkest hour precedes the dawn, so the climax of man’s direst need is the precursor of the day-spring of God’s saving power. And so now, when “at evening time” they shall be expecting the gross darkness of night to set in, suddenly they shall be flooded with the light of God’s salvation. This second half of Zechariah 14:7 is to Zechariah 14:6-7 (a) what Zechariah 14:3 is to Zechariah 14:1-2. In each case the brightness of the Theophany dispels the darkness of despair.