But why do so? At times in the past few decades, some individuals have attempted to make the argument that the use of black is contrary to Christian hope in the resurrection of the dead. Accordingly, some of these same individuals have agitated against the use of black -- even violet -- for these occasions, despite the Church's continued use of that liturgical colour. In response, I would point out that this is not a case of either-or, but rather one of both-and. While Christians are indeed a people of hope rooted in the resurrection, this does not invalidate the natural emotional response of sorrow or mourning, nor that fact that we are likewise to be aware of the reality of sin, death and judgement. Such awareness and reserve is simply that, an awareness and reserve which springs from a recognition of a genuine spiritual reality, and the mere fact of this cannot be equated with hopelessness or an insufficient hope in the resurrection of the dead. In point of fact, not giving adequate recognition to these realities is itself a problem.
If we look at the Church's liturgical year, we see how it brings with it times of feasting as well as times of fasting; it brings times of exuberance and joy and times of more sombre reserve, penance and mourning. The liturgies of Holy Week alone give a particularly condensed example of this. Each of these parts bring to bear and teach of particular aspects within their appointed times and on their appointed occasions, also necessarily understood in relation to and as part of the greater whole. The loss of any of these parts results in an incomplete picture.
The use of black, which corresponds to the recognition of sorrow and mourning, sin, death and judgement, is one manifestation or part of this fuller picture. (And at this point, I would note this is being considered primarily within the liturgical and cultural context of the West.)
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As a symbol then, the use of black speaks strongly and poignantly on a variety of levels and its use is therefore both meritorious and to be encouraged.
See also: The Symbolism Unbleached Beeswax Candles