The Catechism reminds us that prayer involves much more than our soul, “Whether prayer is expressed in words or gestures, it is the whole man who prays” (CCC 2562).
For this reason the Church’s public forms of worship contain numerous elements that are visible and engage our bodily senses. The Catechism teaches us that, “In human life, signs and symbols occupy an important place. As a being at once body and spirit, man expresses and perceives spiritual realities through physical signs and symbols. As a social being, man needs signs and symbols to communicate with others, through language, gestures, and actions. The same holds true for his relationship with God” (CCC 1146).
To help engage all of our senses during the celebration of Mass, lifting up our bodies and souls to God, the Church for centuries has used incense as an important exterior sign.
Incense was a vital part of worship for many ancient religions, including the Jewish worship of God.