10 Day and night they prowl about on its walls; malice and abuse are within it.

Read Psalm 55:10 Using Other Translations

Day and night they go about it upon the walls thereof: mischief also and sorrow are in the midst of it.
Day and night they go around it on its walls, and iniquity and trouble are within it;
Its walls are patrolled day and night against invaders, but the real danger is wickedness within the city.