[169.] Whenever an abuse is committed in the celebration of the sacred Liturgy, it is to be seen as a real falsification of Catholic Liturgy. St Thomas wrote, “the vice of falsehood is perpetrated by anyone who offers worship to God on behalf of the Church in a manner contrary to that which is established by the Church with divine authority, and to which the Church is accustomed”.
[170.] In order that a remedy may be applied to such abuses, “there is a pressing need for the biblical and liturgical formation of the people of God, both pastors and faithful”, so that the Church’s faith and discipline concerning the sacred Liturgy may be accurately presented and understood. Where abuses persist, however, proceedings should be undertaken for safeguarding the spiritual patrimony and rights of the Church in accordance with the law, employing all legitimate means.
[171.] Among the various abuses there are some which are objectively graviora delicta or otherwise constitute grave matters, as well as others which are nonetheless to be carefully avoided and corrected. Bearing in mind everything that is treated especially in Chapter I of this Instruction, attention should be paid to what follows.
1. Graviora delicta
[172.] Graviora delicta against the sanctity of the Most August Sacrifice and Sacrament of the Eucharist are to be handled in accordance with the ‘Norms concerning graviora delicta reserved to the Congregation for the Doctrine of the Faith’, namely:
a) taking away or retaining the consecrated species for sacrilegious ends, or the throwing them away;
b) the attempted celebration of the liturgical action of the Eucharistic Sacrifice or the simulation of the same;
c) the forbidden concelebration of the Eucharistic Sacrifice with ministers of Ecclesial Communities that do not have the apostolic succession nor acknowledge the sacramental dignity of priestly Ordination;
d) the consecration for sacrilegious ends of one matter without the other in the celebration of the Eucharist or even of both outside the celebration of the Eucharist.
2. Grave Matters
[173.] Although the gravity of a matter is to be judged in accordance with the common teaching of the Church and the norms established by her, objectively to be considered among grave matters is anything that puts at risk the validity and dignity of the Most Holy Eucharist: namely, anything that contravenes what is set out above in nn. 48-52, 56, 76-77, 79, 91-92, 94, 96, 101-102, 104, 106, 109, 111, 115, 117, 126, 131-133, 138, 153 and 168. Moreover, attention should be given to the other prescriptions of the Code of Canon Law, and especially what is laid down by canons 1364, 1369, 1373, 1376, 1380, 1384, 1385, 1386, and 1398.
3. Other Abuses
[174.] Furthermore, those actions that are brought about which are contrary to the other matters treated elsewhere in this Instruction or in the norms established by law are not to be considered of little account, but are to be numbered among the other abuses to be carefully avoided and corrected.
[175.] The things set forth in this Instruction obviously do not encompass all the violations against the Church and its discipline that are defined in the canons, in the liturgical laws and in other norms of the Church for the sake of the teaching of the Magisterium or sound tradition. Where something wrong has been committed, it is to be corrected according to the norm of law.