People inspired by evil desires and informed by false ideas want nothing more than to attack and destroy the things that are good and true in others. In an abstract sense, it is the nature of evil to attack good, and is the nature of falsity to attack truth. And since the most effective way to attack something is by surrounding it, coming at it from all sides and cutting off escape, the act of “surrounding” in the Bible is associated with attacks by evil and falsity. If as a child you ever faced a bully, this will make sense. Nothing a victim says or does do any good; everything gets turned against him; any word or action can be twisted into an excuse for a physical attack. You can in a way be "surrounded" by one person.