A while back I had a correspondence regarding votive lamps in early Christian churches.
This started with an enquiry regarding a text in II Enoch 45: “If anyone makes lamps numerous in front of the face of the Lord, then the Lord will make his treasure stores numerous in the highest Kingdom.”
I couldn’t shed a lot of light on this text, but more generally I observed that whereas lights are brought in for any Graeco-Roman meal lasting into the hours of darkness, thinking of Traditio apostolica and of Tertullian Apol. 39 inter alia, the burning of a perpetual light is something different.
I was able to cite a few texts; Tertullian (Apol. 35) didn’t think much of burning lamps during the day, and the same attitude persists in the Synod of Elvira c34 forbidding burning candles in cemeteries during the day: Cereos per diem placuit in coemeterio non incendi, inquietandi enim sanctorum spiritus non sunt. Qui haec non observaverint arceantur ab ecclesiae communione. Whereas this applies to cemeteries, and not churches, it does tell us that lights were burnt in cemeteries. This may relate to burial at night, (note that in the Acta of Cyprian the body is borne to the cemetery by the light of candles and torches) but may also indicate that lights were kept lit in the cemeteries beyond the time of burial and that burial might be accompanied by lights even during the day. The accompaniment of candles to the grave of Macrina (Greg. Naz. Vit. Macr. 994C) is less obviously taking place at night.
Things are much clearer towards the end of the fourth century. Paulinus refers to lights burning night and day (De S. Felice natal. 3) (PL61.467), and there is dispute between Jerome and Vigilantius (Jerome adv. Vigilantium) in part over the very issue of burning lamps in the martyria. This leads me to suspect that the votive lamp in churches originated in the martyria, and that this in turn originated from the custom of burning lights in the cemeteries. Dix (Shape of the liturgy, 419) states that “perpetually burning lights at the martyrs’ tombs are found before the end of the fourth century”, but gives no reference for this (unless he is mindful of Jerome, whom he cites in the following pages.) I would not put much confidence in the report of Anastasius Bibliothecarius that Constantine provided a massive pharum to burn before the tomb of Peter (PL127 1518-19), but it is significant nonetheless that this perpetual light is placed before a martyr’s tomb.
I was reminded of this reading an apocryphal Vita of Herakleidios from (6th century?) Cyprus, where it is said that “The Father Mnason, arriving at the same time as us, prayed a great prayer, and taking oil from the un-extinguished (ἀσβέστου) lamp he put it on the father Heracleides and anointed him entirely (συνήλειψεν αὐτὸν ὅλον.)”
On this F. Halkin, “Les actes apocryphes de Saint Héraclide de Chypre, disciple de l’Apôtre Barnabé” Analecta Bollandiana 82 (1964), 133-170, at 165, comments: “Une lampe á huile qu’on n’éteint jamais, voila une attestation rare, sinon unique, de usage des « veilleuses » ou lampes du sanctuaire. Je ne trouve rien sur cet usage dans le Dictionnaire d’archéologie chrétienne et de liturgie, ni dans le vieux Thesaurus de Suicerus, ni á l’article ἄσβεστος du Patristic Greek Lexicon.” Hopefully this goes some way to filling the void.