Institutio generalis Missalis Romani

The chair of the priest celebrant must signify his office of presiding over the gathering and of directing the prayer. Thus the best place for the chair is in a position facing the people at the head of the sanctuary, unless the design of the building or other circumstances impede this: for example, if the great distance would interfere with communication between the priest and the gathered assembly, or if the tabernacle is in the center behind the altar. Any appearance of a throne, however, is to be avoided.^{119Cf. Sacred Congregation of Rites, Instruction Inter Oecumenici, On the orderly carrying out of the Constitution on the Sacred Liturgy, 26 September 1964, no 92: AAS 56 (1964), p. 898.} It is appropriate that, before being put into liturgical use, the chair be blessed according to the rite described in the Roman Ritual.^{120Cf. The Roman Ritual, Book of Blessings, editio typica, 1984, Order for a Blessing on the Occasion of the Installation of a New Cathedra or Presidential Chair, nos. 880-899.} Likewise, seats should be arranged in the sanctuary for concelebrating priests as well as for priests who are present for the celebration in choir dress but who are not concelebrating. The seat for the deacon should be placed near that of the celebrant. Seats for the other ministers are to be arranged so that they are clearly distinguishable from those for the clergy and so that the ministers are easily able to fulfill the function entrusted to them.^{121Cf. Sacred Congregation of Rites, Instruction Inter Oecumenici, On the orderly carrying out of the Constitution on the Sacred Liturgy, 26 September 1964, no. 92: AAS 56 (1964), p. 898.}