I've been meaning to post this quote for quite a while. I think there is a common misunderstanding between civility and sanctification. Just because one is a calm and restrained person does not mean one is growing in the grace of sanctification. Consider this:
The mortification of sin consists not in the improvement of a quiet, sedate nature. Some men have an advantage by their natural constitution so far as that they are not exposed to such violence of unruly passions and tumultuous affections as many others are. Let now these men cultivate and improve their natural frame and temper by discipline, consideration and prudence, and they may seem to themselves and others very mortified men, when, perhaps, their hearts are a standing sink of all abominations. Some man is never so much troubled all his life, perhaps, with anger and passion, nor does trouble others, as another is almost every day; and yet the latter has done more to the mortification of sin than the former. Let not such persons try their mortification by such things as their natural temper gives not life or vigor to. Let them bring themselves to self-denial, unbelief, envy, or some such spiritual sin, and they will have better view of themselves. (Mortification of Sin, John Owen in Overcoming Sin and Temptation, p. 70).
You see just because your temperament is a Clark Kent and not a Wolverine does not mean that you have progressed further in your sanctification. This is personal to me because I tend to be rather reserved in my display of emotions. I would not say I am emotional distant or detached however, I do appreciate the benefit of being in control of my emotional state. I prefer reasoned discourse and clear headed thinking as opposed to obsessive outbursts and displays. Even as a young man I tended to hold less respect for those who did not have self control. Self-control is of course a fruit of the Spirit but it is easy to manufacture personal outward control particularly if we have a mild demeanor. Manufacturing personal control over our state and responses does not automatically entail personal sanctification and mortification of the flesh. In other words, just because I seem controlled on the outside does not mean I am not a torrid mess of scummy sins on the instead. Don't confuse controlling the outside with cleaning out the inside. We should turn inward and take stock of our heart being careful to identify its true ailments that do indeed run deep.