From my experience, and I've heard other Christians say they believe this,I would ask if the devil"plants" certain people in our lives, especially at specific times, to cause "problems.",and frustrations for us.Like, {has this happened to you?}you're at a point where you're just about to "turn a corner" on something, OR something looks like it'll go off without a hitch,and you say,"Ah, finally!"when just "at the wrong time", a certain person "appears" into your situation, and what do you know?They present a problem into your "perfect situation".Sometimes it's the same person who always seems to be "in the wrong place at the wrong time",almost like it's their job.How can they know it's the "wrong time",you ask? They as humans can't BUT there's someone who might, thereby raising the question,does the devil not just work against us alone, or does he "send" some people at the "right time" to cause us headaches and problems?Because I somehow think it happens maybe too much to be "coincidence."Like I say, sometimes one "pain in the butt" is enough, or over time it could be different people.So does the devil send these people "on a mission" to put problems in our lives?I would say yes. Think so?