Light, as the New Catholic Encyclopedia notes, signifies “joy, optimism, goodness, purity, beauty, festiveness, dignity and life. It is opposed to darkness, which signifies sadness, gloom, desolation, death, ignorance, error, and evil in general.” Christians also find in light the symbol of “truth, faith, wisdom, virtue, grace, divine life, charity, ardor of prayer, sacred presence and the beatific vision.”
Light is created by God. “Then God said ‘Let there be light,’ and there was light. God saw how good the light was” (Gen. 1:3-4). God manifests himself in the burning bush (Ex. 3:2). He dwells in unapproachable light (1 Tim. 6:16). He is light and in him there is no darkness (1 John 1:5). The Holy of Holies is lighted with the seven-branched candle stand (Lev. 24:2-4).
The early Church saw light in use in pagan rites. Lamps, candles, and fires were used to venerate the gods, the dead, and the emperor. The use was so pervasive that the Church was inhibited in using candles in its own rites. Christians attempted to avoid confusion and syncretism by confining candles to the practical matter of household illumination.
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A critic of candles in the Church reveals in himself a simplistic or puritanical mindset. The widespread use of light in worship reflects a truly human appreciation for the appropriateness of the symbol. The inability of someone to perceive this reveals a kind of blindness.