4. is—rather, "was." This assigns the reason why He has thus destroyed the foe (Zep 3:8).
my redeemed—My people to be redeemed.
day … year—here, as in Isa 34:8; 61:2, the time of "vengeance" is described as a "day"; that of grace and of "recompense" to the "redeemed," as a "year."