7 As to the question of tapers, however, we do not, as you in vain misrepresent us, light them in the daytime, but by their solace we would cheer the darkness of the night, and watch for the dawn, lest we should be blind like you and sleep in darkness. And if some persons, being ignorant and simple minded laymen, or, at all events, religious women— of whom we can truly say, “I allow that they have a zeal for God, but not according to knowledge”— adopt the practice in honour of the martyrs, what harm is thereby done to you?
Once upon a time even the Apostles pleaded that the ointment was wasted, but they were rebuked by the voice of the Lord. Christ did not need the ointment, nor do martyrs need the light of tapers; and yet that woman poured out the ointment in honour of Christ, and her heart's devotion was accepted. All those who light these tapers have their reward according to their faith, as the Apostle says: “Let every one abound in his own meaning.” Do you call men of this sort idolaters? I do not deny, that all of us who believe in Christ have passed from the error of idolatry.
For we are not born Christians, but become Christians by being born again. And because we formerly worshipped idols, does it follow that we ought not now to worship God lest we seem to pay like honour to Him and to idols? In the one case respect was paid to idols, and therefore the ceremony is to be abhorred; in the other the martyrs are venerated, and the same ceremony is therefore to be allowed. Throughout the whole Eastern Church, even when there are no relics of the martyrs, whenever the Gospel is to be read the candles are lighted, although the dawn may be reddening the sky, not of course to scatter the darkness, but by way of evidencing our joy. And accordingly the virgins in the Gospel always have their lamps lighted.
And the Apostles are told to have their loins girded, and their lamps burning in their hands. And of John Baptist we read, “He was the lamp that burns and shines”; so that, under the figure of corporeal light, that light is represented of which we read in the Psalter, “Your word is a lamp unto my feet, O Lord, and a light unto my paths.”
Source: Against Vigilantius (New Advent)