SYNOD. — It is the legitimate assembly, convoked by the bishop, of the priests and clerics of his diocese and of others who are obliged to attend, for the purpose of discussing and deliberating on matters pertaining to pastoral care. A particular object of study for the synod are the papal constitutions, the prescriptions of the Roman Congregations, the statutes of previous bishops, and moreover “to establish what it shall judge necessary and useful for correcting vices, promoting virtue, reforming depraved morals, and restoring or fostering ecclesiastical discipline.”
Based on the definition just formulated, and compiled by Benedict XIV in *De Synodo dioecesana*, the synod must always be considered a diocesan convocation, in contrast to a Council, which, whether ecumenical or particular, is an assembly of all the bishops of the Catholic orb or, in the case of a regional or provincial council, a meeting of several bishops. The fundamental difference between a Council and a synod lies in the power involved: in a conciliar assembly this is legislative, whereas in a synod it is merely consultative, since the sole legislator is the bishop, who alone has the right to ratify the constitutions, excluding collective suffrage (can. 362 CIC). On this principle, the legitimacy of the synod is contingent upon the personal presence of the bishop or of the vicar general who has received a mandate from the diocesan bishop. It is also obvious that the capitular vicar has no power to convoke a synod.
Synodal assemblies have a remote origin in the Church: the first seems to have been convoked by Pope Siricius in Rome in 387; originally, however, they differed from councils only in their purpose, since the terms, taken etymologically, are synonymous. The Fourth Lateran Council of 1215 laid down the first precise norms to prevent any possibility of confusion with councils. Subsequently, the Council of Trent greatly enhanced the importance of the synod by imposing upon bishops the obligation to hold it annually (sess. XXIV, *De ref.*, cap. 2). It was only in the 17th century that synodal meetings came to a halt, due to the accusation of Jansenism that the Synod of Pistoia of 1786, convoked by Bishop Scipione de' Ricci (v.), incurred from Pope Pius VI in the constitution *Auctorem fidei* of 1794.
The CIC has moderated the norms laid down by the Council of Trent, extending the obligation to convoke the synod to once every ten years, and this, as some authors have observed, because the existing canonical legislation, being more perfect, provides more concretely for the spiritual needs of the clergy and the faithful. According to can. 356 § 2, if the bishop governs several dioceses *aequo principaliter*, it is sufficient to convoke a single synod, which must always be celebrated in the cathedral church, *nisi aliud rationalis causa suadeat* (can. 357 § 2). Those obliged to attend the synod, unless legitimately impeded, are the vicar general, the canons of the cathedral church and the diocesan consultors, the rector of the diocesan seminary (at least the major seminary), the deans, a member of collegiate churches elected by the chapter, the pastors of the city where the synod is celebrated, at least one pastor from each deanery, the abbots *in regimine*, and one of the superiors of each clerical religious institute residing in the diocese, designated by the provincial. It is left instead to the discretion of the Ordinary to convoke canons, pastors, religious superiors, and other priests of the diocese, excluding however those necessary for the care of souls. The Ordinary may apply penalties to those who are obliged to attend (can. 359 § 2) but in fact do not attend without having informed the bishop of the reasons that prevented their participation. Before the sessions of the synod, the bishop convokes the commissions, and the participants are given a draft of the constitutions that are to be discussed (can. 360 § 1-2).
The term synod is also used in the Waldensian Church, where it is an annual legislative assembly composed of ministers and laypersons, with either deliberative or merely consultative vote.