if you are bothered by it then don't respond - what you give energy to will grow bigger. what you take focus away from eventually shrinks!
devil's advocates motives (conscious or not) usually are:
just there to toy with your mind
to get you to see the other side of the debate cause they actually do care about your evolution (hence the 'source' reference - someone's been watching too much matrix)
pushing all the buttons hoping someone will push their's just as hard so they can in turn figure themselves out! and evolve....
it's all about interpretation. the cards are in your hand lapis!