Jamieson, Fausset and Brown on Ezekiel 21:3

3. righteous ... wicked--not contradictory of Eze 18:4, 9 and Ge 18:23. Ezekiel here views the mere outward aspect of the indiscriminate universality of the national calamity. But really the same captivity to the "righteous" would prove a blessing as a wholesome discipline, which to the "wicked" would be an unmitigated punishment. The godly were sealed with a mark (Eze 9:4), not for outward exemption from the common calamity, but as marked for the secret interpositions of Providence, overruling even evil to their good. The godly were by comparison so few, that not their salvation but the universality of the judgment is brought into view here.