Part II, Article 6. Liturgical Celebration
§ 1. Liturgical actions must always clearly manifest the unity of the
People of God as a structured communion. Thus there exists a close
link between the ordered exercise of liturgical action and the
reflection in the liturgy of the Church's structured nature.
This happens when all participants, with faith and devotion, discharge
those roles proper to them.
§ 2. To promote the proper identity (of various roles) in this area,
those abuses which are contrary to the provisions of canon 907 are to be
eradicated. In eucharistic celebrations deacons and non-ordained members
of the faithful may not pronounce prayers - e.g. especially the
eucharistic prayer, with its concluding doxology - or any other parts of
the liturgy reserved to the celebrant priest. Neither may deacons or
non-ordained members of the faithful use gestures or actions which are
proper to the same priest celebrant. It is a grave abuse for any member
of the non-ordained faithful to "quasi preside" at the Mass while
leaving only that minimal participation to the priest which is necessary
to secure validity.
In the same way, the use of sacred vestments which are reserved to
priests or deacons (stoles, chasubles or dalmatics) at liturgical
ceremonies by non-ordained members of the faithful is clearly unlawful.
Every effort must be made to avoid even the appearance of confusion
which can spring from anomalous liturgical practices. As the sacred
ministers are obliged to wear all of the prescribed liturgical vestments
so too the non-ordained faithful may not assume that which is not proper
To avoid any confusion between sacramental liturgical acts presided over
by a priest or deacon, and other acts which the non-ordained faithful
may lead, it is always necessary to use clearly distinct ceremonials,
especially for the latter.