By “Mass with a congregation” is meant a Mass celebrated with the participation of the faithful. It is moreover appropriate, whenever possible, and especially on Sundays and holy days of obligation, that the celebration of this Mass take place with singing and with a suitable number of ministers.95Cf. Sacred Congregation of Rites, Instruction Eucharisticum mysterium, On the worship of the Eucharist, 25 May 1967, no. 26: AAS 59 (1967), p. 555; Sacred Congregation of Rites, Instruction Musicam sacram, On music in the Liturgy, 5 March 1967, nos. 16, 27: AAS 59 (1967), pp. 305, 308. It may, however, also be celebrated without singing and with only one minister.
If a deacon is present at any celebration of Mass, he should exercise his office. Furthermore, it is desirable that, as a rule, an acolyte, a lector, and a cantor should be there to assist the priest celebrant. In fact, the rite to be described below foresees a greater number of ministers.