§ 1. On The Valid And Licit Matter Of Bread

170. 1. Valid matter of bread. For validly confecting the sacrament, it is required that the bread a) be made from wheaten flour and b) natural water, and that c) it be baked by fire.

Therefore it is required:

a) That the flour be wheaten; therefore matter of another species is invalid, for example, that which is made from barley,²² rye,²³ maize,²⁴ oats,²⁵ rice,²⁶ millet,²⁷ peas,²⁸ beans,²⁹ potatoes, and so forth. Valid matter, however, is flour taken from diverse accidental varieties of wheat, for example, common wheat, durum wheat, turgid wheat, spelt wheat, and so forth. Therefore, true wheat of any region and any variety suffices.

b) It is necessary that the wheaten flour be mixed with natural water. Therefore, if another liquid, for example, milk, wine, or oil, is mixed in a notable quantity, such as one third, the matter is invalid; but if such a mixture is made in a small quantity, the matter is indeed illicit but not invalid. Likewise, salt, sugar, or another seasoning is not to be added to the flour to be baked, since absolutely every mixture is illicit. On the other hand, it is not lawful, for the purpose of obtaining very white and beautiful hosts, to extract all the gluten from the flour so that something like starch is obtained. For gluten appears to pertain to bread, just as alcohol pertains to wine. It is lawful, however, to extract only a part of the gluten (cf. Holy Office, June 25, 1852, Collectan. de Prop. Fide, n. 1076).

c) The dough kneaded from wheaten flour and natural water is to be baked in such a way that it becomes true bread. Hence, if the dough is raw or is merely cooked in the manner of porridge, pastry, or cake, it is not true bread nor valid matter capable of being consecrated.

²² German: Gerste; French: orge.

²³ German: Roggen; French: seigle.

²⁴ German and French: Mais.

²⁵ German: Hafer; French: avoine.

²⁶ German: Reis.

²⁷ German: Hirse; French: millet.

²⁸ German: Erbsen; French: pois.

²⁹ German: Bohnen; French: fèves.

171. 2. Licit matter of bread. For licitly confecting the Eucharist, it is required:

a) That unleavened bread be employed in the Latin rite, but leavened bread in the Eastern rite.³⁰

The Latin Church uses unleavened bread because Christ Himself, instituting the Eucharist during the days of unleavened bread, appears to have employed unleavened bread. The obligation of consecrating unleavened bread is so grave for Latin priests that in only one case is the consecration of leavened bread certainly lawful for them, namely, to complete the sacrifice of a Mass already begun if unleavened bread is altogether lacking.³¹ Hence, according to the opinion which St. Alphonsus³² calls common and more probable, not even for giving Viaticum to a sick person could a Latin priest in a case of necessity consecrate leavened bread. But the opposite opinion appears probable and safe, since the precept of receiving Viaticum is derived from divine law, as will be said below. Now, a precept of divine law prevails over a precept of ecclesiastical law prohibiting consecration with leavened bread.³³

Note. Although both Latin and Eastern priests are bound under grave obligation to consecrate unleavened or leavened bread according to the rite proper to each, and indeed "wherever they celebrate Mass," nevertheless, "where necessity urges and no priest of a different rite is present, it will be lawful for an Eastern priest who uses leavened bread to administer the Eucharist consecrated with unleavened bread, and conversely for a Latin priest, or an Eastern priest who uses unleavened bread, to administer it with leavened bread; but each is to observe his own rite of administering." Thus Pius X.³⁴ Indeed, to all the faithful of any rite the faculty is given, for the sake of devotion, to receive the Eucharistic sacrament confected in any rite. Thus again Pius X,³⁵ who thereby further increased the liberty in this matter already granted by Leo XIII in the Constitution Orientalium dignitas of November 30, 1894. The Code of Canon Law, c. 866, § 1, establishes the same. Each person, however, is to receive Easter Communion and, a fortiori, Viaticum in his own rite and from his own pastor or the latter's delegate, insofar as this is morally possible.³⁶

b) The host to be consecrated must be fresh, clean, intact, and circular in form.

The host must be fresh, and therefore it is not lawful to consecrate hosts already made a month before. The Sacred Congregation of Rites on December 16, 1826,³⁷ says that the custom of consecrating species made three months earlier in winter and six months earlier in summer is to be eliminated. The same Sacred Congregation of Rites on September 12, 1884,³⁸ in response to doubt 2, "Can the custom of renewing the most holy Eucharist once or twice a month be retained, although according to the Ceremonial of Bishops the same most holy Eucharist ought to be renewed every week?" replied: "Let the prescription of the Ceremonial of Bishops, l. 1, c. 6, § 2, be observed." Now, the Ceremonial of Bishops, loc. cit., establishes that the most holy Eucharist "be changed and renewed at least once a week." Nevertheless, this statute does not always appear to bind under grave obligation; accordingly, when a just cause exists and danger of corruption is absent, it suffices to renew the Eucharistic species every fortnight.³⁹ If, however, the climate is very humid or hot, the Eucharistic species must be changed more frequently, lest they become moldy.

The hosts to be consecrated must be not only fresh but also clean and intact. Hence it would be a grave irreverence if a priest, without urgent necessity, were to consecrate a host notably broken or stained. But if the stain or fracture is not so notable and no scandal arises, a priest who consecrates such a host does not sin gravely. St. Alphonsus notes:⁴⁰ "If, however, the fracture [or stain] is discovered after the offertory, such a host will licitly be consecrated, unless scandal of the people is feared."

The shape of the host to be consecrated must be circular in the Latin Church, but square in the Greek Church, or triangular for small hosts. The host employed in Mass or in the monstrance must be larger. Its diameter is to be 6-9 centimeters. St. Alphonsus teaches that, when a larger host is lacking, a priest can celebrate Mass with a smaller host even for devotion alone, provided, however, that he forestalls scandal of the people.⁴¹ Small hosts intended for the Communion of the laity are not to be excessively small and thin; their diameter is to be about 3 centimeters. For if these hosts are excessively small and thin, the distribution of Communion becomes very difficult and can scarcely be performed without inconveniences. Rubricists are accustomed to express the qualities of the host to be consecrated in these verses:

White, wheaten and thin, not large, and round, May Christ's host be unleavened and not broken.

Note. Let the priest diligently take care that those who bake hosts be persons excelling in diligence, piety, and fidelity, and that they employ pure wheat and pure water.

³⁰ There are, however, certain Eastern Christians, such as the Armenians and Maronites, who use unleavened bread. Cf. Sacred Congregation for the Propagation of the Faith, May 20, 1838.

³¹ St. Alphonsus (Theol. mor., l. 6, n. 203) thinks that a Latin priest traveling through Greece can celebrate either with leavened or with unleavened bread. This opinion can scarcely be maintained now, since the Code of Canon Law, c. 816, establishes: "In the celebration of Mass a priest must employ unleavened or leavened bread according to his own rite, wherever he celebrates Mass."

³² Loc. cit.

³³ Thus also Cappello, De sacram., n. 281.

³⁴ Constitution Tradita, September 14, 1912; cf. Code of Canon Law, c. 851.

³⁵ Loc. cit.

³⁶ Cf. Sacred Congregation for the Propagation of the Faith, March 27, 1916, nn. 11 and 12 (Acta Apostolicae Sedis VIII, 106); Code of Canon Law, c. 866.

³⁷ Decr. auth., n. 2650.

³⁸ Ibid., n. 3621.

³⁹ Cf. Benedict XIV, Constitution Etsi pastoralis, May 26, 1742, § 6, n. 4.

⁴⁰ Theol. mor., l. 6, n. 204.

⁴¹ Ibid., n. 205.