We do not know exactly when the use of incense was first introduced into our Mass or other liturgical rites. In Judaism, incense was included in the thanksgiving offerings of oil, rain, fruits, wine (cf. Numbers 7:13-17). The Lord instructed Moses to build a golden altar for the burning of incense (cf. Exodus 30:1-10), which was placed in front of the veil to the entrance of the meeting tent where the Ark of the Covenant was kept. At the time of the early Church, the Jews continued to use incense in their own Temple rituals, so it would be safe to conclude that the Christians would have adapted its usage for their own rituals.
We know there were very pragmatic reasons why the early Christians in Rome used incense. To avoid persecution they were forced to hold their services deep in the catacombs among the rotting corpses of the dead. You can only imagine the stench in those confined spaces where the burning of incense would have bought some relief.
Today the purpose of incensing and the symbolic value of the smoke is that of purification and sanctification. The smoke symbolizes the prayers of the faithful drifting up to heaven: the Psalmist prays, “Let my prayer come like incense before you; the lifting up of my hands, like the evening sacrifice” (Psalm 141). In the General Instruction of the Roman Missal incense may be used during the entrance procession; at the beginning of Mass, to incense the altar; at the procession and proclamation of the Gospel; at the offertory, to incense the offerings, altar, priest and people; and at the elevation of the Sacred Host and chalice of Precious Blood after the consecration.
Incense also creates the ambiance of heaven; the usage of incense adds a sense of solemnity and mystery to the Mass. The visual imagery of the smoke and the smell remind us of the transcendence of the Mass which links heaven with earth, and allow us to enter into the presence of God.
But I just can’t help but feel a solidarity with our fellow Christian brothers and sisters suffering persecution all those years ago in the Rome, when the incense is lit on a Sunday morning at St. Andrew’s.